I beat the game, and by the end I was enjoying the experience! Unfortunately, I think possibly due to screen size, at first I didn't see the buttons on how to play, and interaction was a little confusing. I also thought the rerolls were per playthrough, so I didn't use any until the second to last wave.
Are there any healing abilities? I bet not, but maybe a magic staff with a combo of damage, ignore armor, shields, and a minor heal would be interesting?