Really unique concept! I'm one of the people who hates fighting cute enemies so I'm happy we've got this... 'entity' donning a white cloak to fix those enemies up.
I struggled a bit whenever a new enemy was introduced, though, and it does seem like they're introduced quite quickly - maybe it would help to spawn in one enemy of an enemy type to let the player mess around and learn how it works, and then start spawning that enemy type in regular 'waves'?
I could also just be the worst monster healer, heh.