I don't know if it's cookie cutter or meta but I've had great success with AM Cremation necromancer. I league started it and have kept with it. Easiest time with Sirus (A7 max so far) I've had. (To be fair, my success with Sirus is also due to finally clueing into his patterns a bit.)
Build is a little awkward because desecrate -> cremation is a bit like mines. Sometimes I put down a descrate, immediately try to cast cremation and it's like there are no corpses around, cremation never casts. No idea what's going on with that.
Effective with heist doors although I also use void sphere there to "activate" the mobs (damaging attacks alone don't seem to do it, at least in my experience), but don't stand in the door because they'll still fire their initial blasts at it.