My personal experience, I just got a full set of ruined from a single corrupted dome. Keep an eye out for purple drops that look similar to the protectors boxes that the foreign merchant drops.
The essence chance to drop is tied to your hits, not your kills, so taking more hits to kill an enemy actually gives you more chances at drops. It's best to just run in there and stick to your at-wills to get more drops.
As a healer main I welcome the removal of lifesteal - I'm finally relevant in groups. Also, if you're failing demogorgon then you have crappy healers and tanks. I'm only at about 17k item Level and I can do an epic demo run at gold rating with only 1 or 2 downs in the whole team. That requires the tanks to know how to tank…
This. I accidentally traded all my enchants for runestones and now I have over 40 runestone coffers I don't want to open. It'd be nice to be able to trade them back to enchantments and fix my mistake.