Curse stacking poisons with Doedre's Scorn

Setting expectations

No, this is not a new meta breaker and it's not supposed to be. I just wanted a hypster unique way to clear the remaining parts of endgame my current build cannot deal with (maven, uber elder, sanctums)

I also am trying to somewhat contain its budget, it doesn't need to be a league starter but i also would rather not have to farm 100+ divines before being able to get my final voidstones

Build concept

Doedre's Scorn scales added chaos damage for each curse on an enemy. We then use Anathema to scale curse limit through power charges.

We apply curses with 2 cursed on-hit implicits on gloves + 5 self-cast curses with Vixen's + 1 mark on hit for a total of 8 curses, meaning 296 to 568 added chaos damage, 432 on average which is about what a level 28 added chaos support would give you

Since we have a lot of flat we then scale increased throguh Low Tolerance (poisons) and the new Sadism support gem, adding another multiplicative layer with DoT multi and yet another with faster poisons from Apep's Rage

Our mark skill is obviously going to be Alchemist's Mark so that we can make much better use of our super short poisons, making them last around 8+ seconds as ground degen. Added bonus here is that we can get another multiplicative layer to damage by getting mark effect but unless we go pathfinder that's gonna be hard to get

The final piece of the puzzle is the skill selection. To me Hexblast sounds almost obvious albeit a little too meta for my liking: high damage effectiveness, a multiplication layer against hexed enemies and ability to inflict all ailments (meaning we also get a nice bonus burning ground on top of our caustic one)

The numbers

I'm a little hesitant to share this PoB because IT'S VERY MUCH A PROOF OF CONCEPT WIP and i don't want people to just take that at face value and not read this post, but here we go https://pobb.in/Q6-u7R1xDfNb

As you can see a lot of gear slots are still entirely empty and there's a lot of additional items i'm not sure if i want to use

I came for help finishing this build. The damage is there and can be pushed to x10 what it is in the PoB "easily" (covenant + affliction charges) and we can also probably get much more dps by scaling crits but that's not the main issue

The problem

How the fuck do i scale at least passable defences? And furthermore, how do i squeeze damage more efficiently while still being rasonably survivable?

I'm very very bad at finilizing builds in PoB, especially when it comes to defences so i came here asking for help

Keep in mind that i would like to be my "almost bosser" build. I want to use it to get the last two voidstones and do sanctums/ancestors mechanics comfortably since my current build (frost blades trauma stacking jugg) is kinda trash at anything but mapping

Thanks in advance for any idea and/or help