- Theft of Essence +End Proc for Dark Regen (slot for Acc or make sure there's +Acc in the build to help this hit more/fire more)
- Unbreakable Guards (at least two) in your resist sets (gives End Discount)
- Impervium Armor (at least two) in your resist sets (gives End Recovery)
- Reactive Defense (5) gives End Disc, although you probably won't have slots for this (just mentioning the set, in case you do)
Depending on how flushed with Inf and resources you are, you can purchase the Armors at a relatively low level and Catalyze them, then last for the rest of you leveling.
One slot Oppressive Gloom, unless you have other plans for it. It really is a "one slot wonder" power.