Relic of the Pact PoB question

So I made this witch character earlier, trying out the new relic of the pact.

POB link
https://pastebin.com/TvrihzG7


To not die to reserving too much life I reserve at most 78% of it. So I'm assuming thats around stage 22 on blood sacrament? 30 is the highest. 50% should then be around stage 15?

I can clear normal trash like its nothing, but as soon as a rare or unique enemy shows up it hits like a wet noodle. Ignite dps should still be around 1 mil with a 1,7 mil initial hit according to the PoB. And with my very late game gear and clusters it should be a 5 mil ignite dps, but its not for whatever reason.

Can anyone explain the "stages"? Or am I right about the stages? Or is the PoB completely wrong?