Suggestions for taking my ED Occultist to the next level?

I've hit a point where I'm not sure how to spend my currency to improve my occultist essence drain character.

I'm really enjoying the league and build and would like to push it as far as I can go, currently have 9 div+ to spend. I want to get lvl23 corrupted gem next, but beyond that searching PoE trade for chase gear for the build has me at a loss as I'm not sure what is possible/ideal in each slot.

The build feels fairly tanky after putting in some investment and sacrificing some DPS on the passive tree, but more defense would be swell. It can speed farm well but single target could be better, understanding thats the nature of the build.

PoB link here
https://pobb.in/ljCIKNfdLISf

Any tips greatly appreciated!