I started with the knight, then I only played with the mage because I liked his summon ability. I enjoyed the game, but there are certain things that annoyed me.
The control scheme is awkward and should be simplified. Mapping the skills to 1-3 would be quicker than cycling through attacks.
The enemies move based on proximity rather than when they see you. They end up taking items I want so I have to move strangely just to stop them from taking them. I ending up spending up to around the 300 upgrade until I only bought itens to help keep myself healthy.
It was worse when my own slime ate the items and gold which I didn't gain the benefits. It wouldn't matter so much if we could switch places in the corridor. I think it wold be better if the slime was automatic and attacked enemies without my command. Although, controling it's attacks against a boss really helped too.
Stairs are also automatic which causes a problem if you defeat the boss in a corridor. It cut out half the level because I was forced to leave early.