HoT Autobomber - mana stacking Elementalist

https://pastebin.com/drmPjQkV

Hi, I've been trying to build around a Herald Thunder autobomber (HoT), using a mana-stacker approach, by combining the "Essence Glutton" necro node via forbbiden jewels (2% base mana/s) and Elementalists (1% base mana/s) from "Mastermind of discord" and Agnostic* to sustain both life and mana.

*Agnostic is provided via Sanctified relic, so it's added under custom modifiers.

HoT is in the Crest of Desire to minimize the mana reservation.

Build is so far decent for clearing t16 maps - the sustain is GREAT compared to the standard HoT build, but the damage is somewhat limited - around 2.3m shaper dps* currently.It's still squishy against physical damage, but I'm not expecting much more improvement in that part.

*By getting an additional curse Atziri's foible corrupt, and a Scorched ground boots implicit, it goes to ~2.9m. I've included this in PoB under second item set.

Looking for some meaningful improvements in case anyone built around this already, since I'm not good at creating builds myself.

https://preview.redd.it/vephsw4892ca1.png?width=1788&format=png&auto=webp&v=enabled&s=8f3efa8a2de470e5c9325b1062df1d78c1f875e2