It's a very good time killing game. The pixel art looks good, althought some interactive objects on map would be better if it looks more "pop". With more content, i think it can grow to a full product for the market.
For example, you can add more dungeon varients (physical resist, magic resist, enviroment damage, broken slot, etc), and character equipments that can customize the slot machine mechanic, or adjust/lock the slot combination.
Looking forward.