The infinite500 addon completely overrode changes to advanced minion mastery and necrotic minions.

I didn't use any of the (improved) grave tree, so I don't know if i500 overrode that, too.
IMHO, the charnel tree seems much more fit for a corrupter.
Blight and physical damage... not really necromancer skills.
Perhaps a "Dark Energy" tree, instead?
Mana Drain (of some sort or another)
Soul Battery (turns a soul into mana)
Dark Conduit (sustain that drains your mana, gives minions better stats)
Vampiric Gift
Totally up to you. (But I'd really like compatability with i500
