
This lead me to think about wdm barb solution for end-game play (T10 lab, sam, deimoss, nithogur, etc)
After my try, I'd like to share 2 setup for barb. The most parts are same, only weapon choice is different. Let me link these items also my char link, and with some details explanation.
Char-link : https://median-xl.com/char/ovoovo
Setup
Helm:
Boarfrost
/
Boarfrost
Assault Helmet (Sacred)
Defense: (2238 - 2561) to (2449 - 2803)
(Barbarian Only)
Required Level: 100
Required Strength: 600
Item Level: 120
25% Chance to cast level 40 Ice Bolt Nova on Melee Attack
20% Attack Speed
Adds 63-125 Cold Damage
+(21 to 25)% to Cold Spell Damage
-50% to Enemy Cold Resistance
+10 to Deathgaze
Weapon Physical Damage +90%
+(87 to 114)% Enhanced Defense
(21 to 25)% to Strength
Socketed (4)
Assault Helmet (Sacred)
Defense: (2238 - 2561) to (2449 - 2803)
(Barbarian Only)
Required Level: 100
Required Strength: 600
Item Level: 120
25% Chance to cast level 40 Ice Bolt Nova on Melee Attack
20% Attack Speed
Adds 63-125 Cold Damage
+(21 to 25)% to Cold Spell Damage
-50% to Enemy Cold Resistance
+10 to Deathgaze
Weapon Physical Damage +90%
+(87 to 114)% Enhanced Defense
(21 to 25)% to Strength
Socketed (4)
Royal Circlet
/
Royal Circlet
Tiara (Sacred)
Defense: (1740 - 1957) to (1968 - 2214)
Required Level: 100
Required Dexterity: 392
Item Level: 105
+2 to All Skills
+50% Damage to Demons
+50% Damage to Undead
+(140 to 170)% Enhanced Defense
(21 to 25)% to All Attributes
Elemental Resists +(25 to 30)%
Physical Resist 5%
(21 to 25)% Magic Find
Socketed (4)
Tiara (Sacred)
Defense: (1740 - 1957) to (1968 - 2214)
Required Level: 100
Required Dexterity: 392
Item Level: 105
+2 to All Skills
+50% Damage to Demons
+50% Damage to Undead
+(140 to 170)% Enhanced Defense
(21 to 25)% to All Attributes
Elemental Resists +(25 to 30)%
Physical Resist 5%
(21 to 25)% Magic Find
Socketed (4)
Witchhunter's Hood
Witchhunter's Attire
(Assassin Claw Set)

Witchhunter's Hood
Cap (Sacred)
Defense: (2136 - 2611) to (2161 - 2642)
Required Level: 90
Required Strength: 250
Item Level: 1
+(80 to 120)% Enhanced Defense
10% to Strength
10% to Dexterity
Maximum Elemental Resists +1%
Elemental Resists +(31 to 40)%
Physical Resist 5%
(16 to 20)% Bonus to Defense
Requirements -50%
Socketed (4)
Cap (Sacred)
Defense: (2136 - 2611) to (2161 - 2642)
Required Level: 90
Required Strength: 250
Item Level: 1
+(80 to 120)% Enhanced Defense
10% to Strength
10% to Dexterity
Maximum Elemental Resists +1%
Elemental Resists +(31 to 40)%
Physical Resist 5%
(16 to 20)% Bonus to Defense
Requirements -50%
Socketed (4)
Witchhunter's Attire
(Assassin Claw Set)
Boarfrost
is for cold pierce if you want to use Sam sword harbinger as your clear skill. I will explain further with some details below.
Boarfrost
Assault Helmet (Sacred)
Defense: (2238 - 2561) to (2449 - 2803)
(Barbarian Only)
Required Level: 100
Required Strength: 600
Item Level: 120
25% Chance to cast level 40 Ice Bolt Nova on Melee Attack
20% Attack Speed
Adds 63-125 Cold Damage
+(21 to 25)% to Cold Spell Damage
-50% to Enemy Cold Resistance
+10 to Deathgaze
Weapon Physical Damage +90%
+(87 to 114)% Enhanced Defense
(21 to 25)% to Strength
Socketed (4)
Assault Helmet (Sacred)
Defense: (2238 - 2561) to (2449 - 2803)
(Barbarian Only)
Required Level: 100
Required Strength: 600
Item Level: 120
25% Chance to cast level 40 Ice Bolt Nova on Melee Attack
20% Attack Speed
Adds 63-125 Cold Damage
+(21 to 25)% to Cold Spell Damage
-50% to Enemy Cold Resistance
+10 to Deathgaze
Weapon Physical Damage +90%
+(87 to 114)% Enhanced Defense
(21 to 25)% to Strength
Socketed (4)
Royal Circlet
is used for Sam sword setup but not use harbinger as clear skill. You can only use harbinger as a TP skill and use EQ as clear skill. With buff in 2.5 of tectonics, in end-game you can obtain like 17% + proc of SoR which is a decent dmg bonus. 
Royal Circlet
Tiara (Sacred)
Defense: (1740 - 1957) to (1968 - 2214)
Required Level: 100
Required Dexterity: 392
Item Level: 105
+2 to All Skills
+50% Damage to Demons
+50% Damage to Undead
+(140 to 170)% Enhanced Defense
(21 to 25)% to All Attributes
Elemental Resists +(25 to 30)%
Physical Resist 5%
(21 to 25)% Magic Find
Socketed (4)
Tiara (Sacred)
Defense: (1740 - 1957) to (1968 - 2214)
Required Level: 100
Required Dexterity: 392
Item Level: 105
+2 to All Skills
+50% Damage to Demons
+50% Damage to Undead
+(140 to 170)% Enhanced Defense
(21 to 25)% to All Attributes
Elemental Resists +(25 to 30)%
Physical Resist 5%
(21 to 25)% Magic Find
Socketed (4)
Witchhunter's Hood
Witchhunter's Attire
(Assassin Claw Set)
is used for 
Witchhunter's Hood
Cap (Sacred)
Defense: (2136 - 2611) to (2161 - 2642)
Required Level: 90
Required Strength: 250
Item Level: 1
+(80 to 120)% Enhanced Defense
10% to Strength
10% to Dexterity
Maximum Elemental Resists +1%
Elemental Resists +(31 to 40)%
Physical Resist 5%
(16 to 20)% Bonus to Defense
Requirements -50%
Socketed (4)
Cap (Sacred)
Defense: (2136 - 2611) to (2161 - 2642)
Required Level: 90
Required Strength: 250
Item Level: 1
+(80 to 120)% Enhanced Defense
10% to Strength
10% to Dexterity
Maximum Elemental Resists +1%
Elemental Resists +(31 to 40)%
Physical Resist 5%
(16 to 20)% Bonus to Defense
Requirements -50%
Socketed (4)
Witchhunter's Attire
(Assassin Claw Set)
The King of Ents
setup which is pretty much similar as wdm bear. Or you can use 
The King of Ents
Labrys (Sacred)
Two-Hand Damage: (291 - 321) to (446 - 527)
(Barbarian Only)
Required Level: 100
Required Strength: 796
Item Level: 120
Strength Damage Bonus: (0.16 per Strength)%
Thunderfury
Treewarden Morph
+1 to Barbarian Skill Levels
50% Attack Speed
+(150 to 200) to Maximum Damage
+(172 to 200)% Enhanced Damage
+(5 to 15) to Rend
+(50 to 100) Life after each Kill
Socketed (6)
Labrys (Sacred)
Two-Hand Damage: (291 - 321) to (446 - 527)
(Barbarian Only)
Required Level: 100
Required Strength: 796
Item Level: 120
Strength Damage Bonus: (0.16 per Strength)%
Thunderfury
Treewarden Morph
+1 to Barbarian Skill Levels
50% Attack Speed
+(150 to 200) to Maximum Damage
+(172 to 200)% Enhanced Damage
+(5 to 15) to Rend
+(50 to 100) Life after each Kill
Socketed (6)
Endless Pride
but personally I recommend 
Endless Pride
Cap (Sacred)
Defense: 1187 to 1201
Required Level: 120
Required Strength: 500
Item Level: 130
Restitution
(Based on Restore Percentage)
+2 to All Skills
+50% Bonus to Defense
Maximum Elemental Resists +3%
Cube with Heavenly Soul: Restore +20%
+4 to Life (Based on Character Level)
+2 to Mana (Based on Character Level)
Elemental Resists +10%
(1 to 50)% Magic Find
Socketed (4)
Cap (Sacred)
Defense: 1187 to 1201
Required Level: 120
Required Strength: 500
Item Level: 130
Restitution
(Based on Restore Percentage)
+2 to All Skills
+50% Bonus to Defense
Maximum Elemental Resists +3%
Cube with Heavenly Soul: Restore +20%
+4 to Life (Based on Character Level)
+2 to Mana (Based on Character Level)
Elemental Resists +10%
(1 to 50)% Magic Find
Socketed (4)
Witchhunter's Hood
Witchhunter's Attire
(Assassin Claw Set)
more because in this barb setup you get 100%DS already so you don't need to use 
Witchhunter's Hood
Cap (Sacred)
Defense: (2136 - 2611) to (2161 - 2642)
Required Level: 90
Required Strength: 250
Item Level: 1
+(80 to 120)% Enhanced Defense
10% to Strength
10% to Dexterity
Maximum Elemental Resists +1%
Elemental Resists +(31 to 40)%
Physical Resist 5%
(16 to 20)% Bonus to Defense
Requirements -50%
Socketed (4)
Cap (Sacred)
Defense: (2136 - 2611) to (2161 - 2642)
Required Level: 90
Required Strength: 250
Item Level: 1
+(80 to 120)% Enhanced Defense
10% to Strength
10% to Dexterity
Maximum Elemental Resists +1%
Elemental Resists +(31 to 40)%
Physical Resist 5%
(16 to 20)% Bonus to Defense
Requirements -50%
Socketed (4)
Witchhunter's Attire
(Assassin Claw Set)
Path of Brutality
, so you get a lot of skills which make 
Path of Brutality
Occult Effigy
Cube Reagent
Cube with Unique Ring/Amulet to Add Bonus
Transforms every +1 to All Skills to +3% Deadly Strike
Item Becomes (Your Class Only)
+10 Required Level
Occult Effigy
Cube Reagent
Cube with Unique Ring/Amulet to Add Bonus
Transforms every +1 to All Skills to +3% Deadly Strike
Item Becomes (Your Class Only)
+10 Required Level
Endless Pride
is not so necessary, for 
Endless Pride
Cap (Sacred)
Defense: 1187 to 1201
Required Level: 120
Required Strength: 500
Item Level: 130
Restitution
(Based on Restore Percentage)
+2 to All Skills
+50% Bonus to Defense
Maximum Elemental Resists +3%
Cube with Heavenly Soul: Restore +20%
+4 to Life (Based on Character Level)
+2 to Mana (Based on Character Level)
Elemental Resists +10%
(1 to 50)% Magic Find
Socketed (4)
Cap (Sacred)
Defense: 1187 to 1201
Required Level: 120
Required Strength: 500
Item Level: 130
Restitution
(Based on Restore Percentage)
+2 to All Skills
+50% Bonus to Defense
Maximum Elemental Resists +3%
Cube with Heavenly Soul: Restore +20%
+4 to Life (Based on Character Level)
+2 to Mana (Based on Character Level)
Elemental Resists +10%
(1 to 50)% Magic Find
Socketed (4)
Witchhunter's Hood
Witchhunter's Attire
(Assassin Claw Set)
you can also expect some nice corruption and more MO space.
Witchhunter's Hood
Cap (Sacred)
Defense: (2136 - 2611) to (2161 - 2642)
Required Level: 90
Required Strength: 250
Item Level: 1
+(80 to 120)% Enhanced Defense
10% to Strength
10% to Dexterity
Maximum Elemental Resists +1%
Elemental Resists +(31 to 40)%
Physical Resist 5%
(16 to 20)% Bonus to Defense
Requirements -50%
Socketed (4)
Cap (Sacred)
Defense: (2136 - 2611) to (2161 - 2642)
Required Level: 90
Required Strength: 250
Item Level: 1
+(80 to 120)% Enhanced Defense
10% to Strength
10% to Dexterity
Maximum Elemental Resists +1%
Elemental Resists +(31 to 40)%
Physical Resist 5%
(16 to 20)% Bonus to Defense
Requirements -50%
Socketed (4)
Witchhunter's Attire
(Assassin Claw Set)
Armor :
Arkaine's Valor
Barb can snapshot bear stance also have other source bonus defense, making this armor become our best choice. 
Arkaine's Valor
Splint Mail (Sacred)
Defense: (9532 - 10839) to (12577 - 14093)
Required Level: 100
Required Strength: 600
Item Level: 120
50% of Your Bonus to Defense Added as Vitality
+1 to All Skills
50% Hit Recovery
+(150 to 200)% Enhanced Defense
+(3000 to 5000) Defense
Physical Resist 10%
Socketed (6)
Splint Mail (Sacred)
Defense: (9532 - 10839) to (12577 - 14093)
Required Level: 100
Required Strength: 600
Item Level: 120
50% of Your Bonus to Defense Added as Vitality
+1 to All Skills
50% Hit Recovery
+(150 to 200)% Enhanced Defense
+(3000 to 5000) Defense
Physical Resist 10%
Socketed (6)
Rings :
Ripstar
X2 for easy good corruption and lot of MO space. We dont need ias or ds from 
Ripstar
Ring
Required Level: 60
Item Level: 60
+0.5625 to Maximum Damage (Based on Character Level)
+20 Life on Melee Attack
Ring
Required Level: 60
Item Level: 60
+0.5625 to Maximum Damage (Based on Character Level)
+20 Life on Melee Attack
Giant's Knuckle
also pr is somehow useless for end-game.
Giant's Knuckle
Ring
Required Level: 100
Item Level: 120
20% Attack Speed
Adds 10-15 Damage
(5 to 10)% Life stolen per Hit
5% Deadly Strike
+25 Life Regenerated per Second
Physical Resist 5%
Ring
Required Level: 100
Item Level: 120
20% Attack Speed
Adds 10-15 Damage
(5 to 10)% Life stolen per Hit
5% Deadly Strike
+25 Life Regenerated per Second
Physical Resist 5%
Amulet:
Dyers Eve
good proc. nice dmg, also +3sk helps 
Dyers Eve
Amulet
Required Level: 100
Item Level: 120
5% Chance to cast level 5 Time Strike on Striking
+2 to All Skills
Adds 15-20 Damage
5% Life stolen per Hit
Elemental Resists +10%
Physical Resist (1 to 10)%
Amulet
Required Level: 100
Item Level: 120
5% Chance to cast level 5 Time Strike on Striking
+2 to All Skills
Adds 15-20 Damage
5% Life stolen per Hit
Elemental Resists +10%
Physical Resist (1 to 10)%
Relic (Cherubim)

Relic
Required Level: 75
5% Life stolen per Hit
+(6 to 13) to Cherubim
(4 to 8)% to Strength
Required Level: 75
5% Life stolen per Hit
+(6 to 13) to Cherubim
(4 to 8)% to Strength
gloves/boots/belt : hono.
weapon:
Maleficence
/ 
Maleficence
Maleficence
Tyrannical Blade
One-Hand Damage: 399 to 450
Required Level: 125
Item Level: 110
Dexterity Damage Bonus: (0.13 per Dexterity)%
Strength Damage Bonus: (0.14 per Strength)%
1% Chance to cast level 20 Orb of Annihilation on Striking
+200% Enhanced Damage
+50 to Harbinger
Lightning Resist -100%
(1 to 5)% Chance to Avoid Damage
+3% to Experience Gained
Maleficence
Tyrannical Blade
One-Hand Damage: 399 to 450
Required Level: 125
Item Level: 110
Dexterity Damage Bonus: (0.13 per Dexterity)%
Strength Damage Bonus: (0.14 per Strength)%
1% Chance to cast level 20 Orb of Annihilation on Striking
+200% Enhanced Damage
+50 to Harbinger
Lightning Resist -100%
(1 to 5)% Chance to Avoid Damage
+3% to Experience Gained
The King of Ents

The King of Ents
Labrys (Sacred)
Two-Hand Damage: (291 - 321) to (446 - 527)
(Barbarian Only)
Required Level: 100
Required Strength: 796
Item Level: 120
Strength Damage Bonus: (0.16 per Strength)%
Thunderfury
Treewarden Morph
+1 to Barbarian Skill Levels
50% Attack Speed
+(150 to 200) to Maximum Damage
+(172 to 200)% Enhanced Damage
+(5 to 15) to Rend
+(50 to 100) Life after each Kill
Socketed (6)
Labrys (Sacred)
Two-Hand Damage: (291 - 321) to (446 - 527)
(Barbarian Only)
Required Level: 100
Required Strength: 796
Item Level: 120
Strength Damage Bonus: (0.16 per Strength)%
Thunderfury
Treewarden Morph
+1 to Barbarian Skill Levels
50% Attack Speed
+(150 to 200) to Maximum Damage
+(172 to 200)% Enhanced Damage
+(5 to 15) to Rend
+(50 to 100) Life after each Kill
Socketed (6)
shield (if you don't use
The King of Ents
) : 
The King of Ents
Labrys (Sacred)
Two-Hand Damage: (291 - 321) to (446 - 527)
(Barbarian Only)
Required Level: 100
Required Strength: 796
Item Level: 120
Strength Damage Bonus: (0.16 per Strength)%
Thunderfury
Treewarden Morph
+1 to Barbarian Skill Levels
50% Attack Speed
+(150 to 200) to Maximum Damage
+(172 to 200)% Enhanced Damage
+(5 to 15) to Rend
+(50 to 100) Life after each Kill
Socketed (6)
Labrys (Sacred)
Two-Hand Damage: (291 - 321) to (446 - 527)
(Barbarian Only)
Required Level: 100
Required Strength: 796
Item Level: 120
Strength Damage Bonus: (0.16 per Strength)%
Thunderfury
Treewarden Morph
+1 to Barbarian Skill Levels
50% Attack Speed
+(150 to 200) to Maximum Damage
+(172 to 200)% Enhanced Damage
+(5 to 15) to Rend
+(50 to 100) Life after each Kill
Socketed (6)
Titan's Blockade





Titan's Blockade
Barbarian Shields
'UmZolLew'
Runeword Level: 110
At least 1 Base Level in Runemaster: Maximum Poison Resist +4%
With 15 Base Levels in Runemaster: 10% Deadly Strike
40% Hit Recovery
Adds 15-25 Damage
Slows Attacker by 10%
+(130 to 150)% Enhanced Defense
+(1000 to 2000) Defense
(20 to 30)% to Strength
20% to Vitality
Maximum Mana +5%
Elemental Resists +35%
Barbarian Shields
'UmZolLew'
Runeword Level: 110
At least 1 Base Level in Runemaster: Maximum Poison Resist +4%
With 15 Base Levels in Runemaster: 10% Deadly Strike
40% Hit Recovery
Adds 15-25 Damage
Slows Attacker by 10%
+(130 to 150)% Enhanced Defense
+(1000 to 2000) Defense
(20 to 30)% to Strength
20% to Vitality
Maximum Mana +5%
Elemental Resists +35%
Playstyle-The King of Ents
The King of Ents
setup is pretty much similar as bear. You need 
The King of Ents
Labrys (Sacred)
Two-Hand Damage: (291 - 321) to (446 - 527)
(Barbarian Only)
Required Level: 100
Required Strength: 796
Item Level: 120
Strength Damage Bonus: (0.16 per Strength)%
Thunderfury
Treewarden Morph
+1 to Barbarian Skill Levels
50% Attack Speed
+(150 to 200) to Maximum Damage
+(172 to 200)% Enhanced Damage
+(5 to 15) to Rend
+(50 to 100) Life after each Kill
Socketed (6)
Labrys (Sacred)
Two-Hand Damage: (291 - 321) to (446 - 527)
(Barbarian Only)
Required Level: 100
Required Strength: 796
Item Level: 120
Strength Damage Bonus: (0.16 per Strength)%
Thunderfury
Treewarden Morph
+1 to Barbarian Skill Levels
50% Attack Speed
+(150 to 200) to Maximum Damage
+(172 to 200)% Enhanced Damage
+(5 to 15) to Rend
+(50 to 100) Life after each Kill
Socketed (6)
Relic (Cherubim)
for clear. The overall dmg on Cherubim is higher than bear, and rend dmg is similar with using SoR for single target. As a barb compare to bear, you get more dodge, and better ias fpa, but lower HP. Overall the performance is pretty similar. One thing good to know is , tree warden hit box is larger than bear. this maybe annoying in some case , like sam fight.
Relic
Required Level: 75
5% Life stolen per Hit
+(6 to 13) to Cherubim
(4 to 8)% to Strength
Required Level: 75
5% Life stolen per Hit
+(6 to 13) to Cherubim
(4 to 8)% to Strength

Playstyle-Maleficence
Maleficence
setup is a little more complex but I like this more personally because I'm tired of bear play. We have 2 choice here : use / not use harbinger. 
Maleficence
Maleficence
Tyrannical Blade
One-Hand Damage: 399 to 450
Required Level: 125
Item Level: 110
Dexterity Damage Bonus: (0.13 per Dexterity)%
Strength Damage Bonus: (0.14 per Strength)%
1% Chance to cast level 20 Orb of Annihilation on Striking
+200% Enhanced Damage
+50 to Harbinger
Lightning Resist -100%
(1 to 5)% Chance to Avoid Damage
+3% to Experience Gained
Maleficence
Tyrannical Blade
One-Hand Damage: 399 to 450
Required Level: 125
Item Level: 110
Dexterity Damage Bonus: (0.13 per Dexterity)%
Strength Damage Bonus: (0.14 per Strength)%
1% Chance to cast level 20 Orb of Annihilation on Striking
+200% Enhanced Damage
+50 to Harbinger
Lightning Resist -100%
(1 to 5)% Chance to Avoid Damage
+3% to Experience Gained
To use harbinger, you have to know some facts of this super-buggy skill because most information you get is not right. Tooltip, charsheet show, etc. All wrong. Here are some facts:
► Show Spoiler
If you want to use harbinger you have to stack some cold pierce which make
Boarfrost
as our best choice. I get 80 cold pierce which is far from enough but I don't have enough time and resource to try to get more. Maybe you can use some hybrid setup ( add more dex point to use 
Boarfrost
Assault Helmet (Sacred)
Defense: (2238 - 2561) to (2449 - 2803)
(Barbarian Only)
Required Level: 100
Required Strength: 600
Item Level: 120
25% Chance to cast level 40 Ice Bolt Nova on Melee Attack
20% Attack Speed
Adds 63-125 Cold Damage
+(21 to 25)% to Cold Spell Damage
-50% to Enemy Cold Resistance
+10 to Deathgaze
Weapon Physical Damage +90%
+(87 to 114)% Enhanced Defense
(21 to 25)% to Strength
Socketed (4)
Assault Helmet (Sacred)
Defense: (2238 - 2561) to (2449 - 2803)
(Barbarian Only)
Required Level: 100
Required Strength: 600
Item Level: 120
25% Chance to cast level 40 Ice Bolt Nova on Melee Attack
20% Attack Speed
Adds 63-125 Cold Damage
+(21 to 25)% to Cold Spell Damage
-50% to Enemy Cold Resistance
+10 to Deathgaze
Weapon Physical Damage +90%
+(87 to 114)% Enhanced Defense
(21 to 25)% to Strength
Socketed (4)
Svalinn


at the meantime you keep your str > dex+ vit). Extra dex also helps for AR since our cold dmg prevent us using heart of stone passive which lead some AR problem.


Svalinn
Shields
'RhalLoOhn'
Runeword Level: 115
-1% to Enemy Elemental Resistances per 150 Dexterity
8% Chance to cast level 7 Life Spark when Blocking
1% Base Block Chance
15% Block Speed
20% Hit Recovery
+(151 to 200)% Enhanced Defense
+(30 to 40) to all Attributes
(15 to 20)% to Dexterity
+200 to Life
Fire Resist +(20 to 25)%
Lightning Resist +(20 to 25)%
Cold Resist +(20 to 25)%
Poison Resist +(20 to 25)%
Fire Absorb (3 to 5)%
Physical Resist 5%
Shields
'RhalLoOhn'
Runeword Level: 115
-1% to Enemy Elemental Resistances per 150 Dexterity
8% Chance to cast level 7 Life Spark when Blocking
1% Base Block Chance
15% Block Speed
20% Hit Recovery
+(151 to 200)% Enhanced Defense
+(30 to 40) to all Attributes
(15 to 20)% to Dexterity
+200 to Life
Fire Resist +(20 to 25)%
Lightning Resist +(20 to 25)%
Cold Resist +(20 to 25)%
Poison Resist +(20 to 25)%
Fire Absorb (3 to 5)%
Physical Resist 5%
Although my cold pierce is not enough but still with this setup I can easily clear T9, not mention to scos or fautz. T10 is a little trouble because the mobs are a little sparse also a lot of phoboss spawn making us flying around style a little dangerous. Also considering element absorb in lab, the insufficient cold pierce makes the dmg a little lower compared to other playstyle.
If you don't want to bother with cold pierce and drop harbinger, you can use EQ as your clear skill too. This dmg performance is not bad. I tried to use this clear T10. Only problem is, the playstyle is a little awkward, you fly to mobs, change skill to EQ and attack. This is not straight forward and annoying.
Both cases for Maleficence you need a single target skill for boss, I recommend
Relic (Divine Judgment)
. Or you can just swap to The King of Ents on off-hand to use rend.
Relic
Required Level: 75
+(9 to 16) to Divine Judgment
+(21 to 25) to Strength
(2 to 4)% to Strength
Required Level: 75
+(9 to 16) to Divine Judgment
+(21 to 25) to Strength
(2 to 4)% to Strength

That's all about my exploration for end-game barb. I drop GT because I feel tired of GT also GT get nerfed. But I think GT is still a decent skill to make use of new 100DS relic. Unfortunately, because my personal computer is too old, I can't record some videos to show the performance. But I did try all these setup so I can safely say all of them are doable. I used these to farm T10 and lvl up to 150.
During the exploration, at first the harbinger dmg makes my very confused ( I add heart of stones since harbinger shows its magic convert) ,also char sheet shown is not right. So I have some discussion and arguments with dev and mod. If anyone interested, here is some my own view on the whole harbinger buggy things:
► Show Spoiler