So, new absolution: I don't feel this is working well. It's keeping the boon under control for low-level characters... by crippling it for high-level characters. I understand the purpose is to prevent spamming it at level 1, but it's really putting Enlightenment out of reach and hurting later joinees who don't have the opportunity to leverage early.
Five layers of absolution grants 20 HP. It used to cost 10 piety; it now costs 30 piety. This is much more sensible for a 1st or 2nd level character, for whom this is a huge bonus. For a higher-level character it's a bit overpriced for the loss of popcorn and inventory space. Its higher cost means it now has a dissonance with Enlightenment. This is also a considerable stealth-nerf to Enlightenment, since it's no longer possible to obtain an appreciable number of beads for enchantment and still having enough piety to pull it off.
I feel that piety cost on its own will not keep this boon under control. Thanks to his conversion piety, GG can fuel pretty much any rational cost at level 1, which is where this boon is a real issue. Absolution, even at its old rock-bottom price, was a non-issue at level 5+. It was a good HP boost, but you paid for it with popcorn and inventory space. I feel any nerf should be targeted at the lower levels.
Having absolution only affect lower-level monsters, having it consume both a bloodstain and a monster, or having the HP scale by player level (presumably with a very different piety structure) would all be great ways to solve this. Tweaking the piety structure just seems to have have amplified GG's worst tendency: the requirement to find him at level 1 to get the best bang for your buck.