I'd really recommend to play at p1 and get to destruction fast, at p8 you're going to waste a lot of time in the first 2 difficulties that can't drop sacred uniques
I'd also recommend maxing skeletal flayers, death fury totem, embalming and nightwalker as those skills all have great synergy with each other and giving a Sol rw bow to your ranger merc to greatly improve your clearspeed
after you resurrect your merc or change her gear she will lose most of her damage due to a d2bug, save&exit fixes this
summon one DF totem to buff whole party, then you can summon 3 of the ones that shoot spells ( you can also replace one of the shooting ones with howling totem if you like )
you also put "move without attacking" on your LMB so you don't accidentally try to melee mobs when trying to move around, but you should be using bend the shadows to move your whole army+totems anyway
you can also make a Nef rw staff to gain teleport skill and keep it on switch to make navigation much easier when you want to teleport behind walls, or across rivers in a3