If you take my advice, the Bloodmage, the equip for him is very standard:
Armor: Queen of glass, tu Ancient armor, tier 6 ofc in dest. A "perfect" is great. For perfect, I mean, -40 all enemy resist.
Helm: TU Crown for -poison resist , or TU mask for some reanimates and poison/fire spell damage.
Boots: TU greaves for more poison and fire spell damage. A "perfect" 1 get 20% for each 1 of them.
Weapon: TU Falchion. Again, a "perfect" 1 gets -20% to fire and poison resist. Nice. Still, a "double mo Falchion" will be an great endgame merc weapon
Amulet: reroll a rare amulet. 2 to all skills, some spell damage, and -fire resist and LAK are great stats.
Gloves: Vilehand is a good idea. Police version, the TU Gauntlets also are good.
Belt: TU Belt. With perfect fire spell damage.
For mistic orbs, you have plenty of room. The bloodmage need at least 15% of teleport when struck for survive in TA. Ofc, mo'ed your gear until get the clasic 350% to defense, and then choose where place the tp when struck orbs. Maybe I post a pic of my merc some day.
For melee mercs act 2... the tu trident sea summoner is mandatoty. Double mo'ed will be great.
armor: TU plate mail : cold proc. Mid to endgame: a "Dragonheart" rw.
boots: tu chain boots
belt: tu heavy belt. mid to endgame, a "Truce" runeword
Helm: tu Crown.
For barb... other day....XD