Hey glad you're enjoying it :D
We will be doing more to help the enemies stand out a bit better, mostly via brightmaps so that they're a bit brighter to see at baseline, and show up clearer when they are attacking. The Dreads (imp like) are a good example of an enemy that definitely blends in a bit too well.
We can definitely look at a scaling pain effect getting more intense as you get closer to death as well (I think you're the first person to raise that?).
Thanks for playing!