I think the distinct lack of enemy diversity is what kills it for me. Even the boss designs are overall lackluster. A bunch of cubes casting spells, or an ice/fire flower. I go to challenge this water goddess thing and instead I fight water squirrels and crabs. That and I can only kill about four bosses a day for rewards.
First going in I thought I would be playing with friends and fighting bosses. Now I've been told not to do that because you don't want friends stealing your chests. Maybe I'm doing things wrong.