[POE2] Saving a Witch build 15 hrs in

I went for a DoT based build (since I love DoT's), and when it was time to pick an ascendancy I was kind of confused since neither mentioned DoT's at all. So I went blood witch, since Inferal seemed to be heavy on the Minion side.

Now here's the problem I've realized:

DoT's don't crit (unless there is an initial Hit)
DoT's don't transfer Leech
Single target Chaos damage doesn't ramp at all until easily after Act 2.

Now I'm stuck on the last boss of Act 2 because I do close to no damage on single target. Not only that, but every spell I cast drains life without any return.

I can manually refund every talent, but that doesn't fix my investment into skillgems, items and Ascendancy....

Is there some trick to Chaos Witch that I've missed?

Same problem, I'm on cruel difficulty but it had been HARD. Like I am 10 levels above content and struggling to cast spells and not die. The health cost per cast and not being able to heal is too much and there is no way to come back from it. I would need 100k+ to get back on track where items sell for 200 gold.