I guessed arbiter is the main problem. About 6 stacks and Apocs, i dont maybe doit it wrong, but i use 2x FS, deplete all runes and have 6stacks of FW, no runic power for DC, no Runic Corruption, and all runes run up, I Rather use Apocs with 6 FW then wait so much time for 2 runes to come and use it for another stacks. But its seem its wrong idea. Dark Transformation delay bcs i wait for mobs, which are needed to nuke down, its seem another bad idea :D
I pop up Army of Death before pull, so you suggest to wait for Bloodlust and then cast Army with Bloodlast up?
Honestly i try Infect