I think the damage output of crossbow and fists are too random. If it takes 1 or 3 hits to take down a minor monster it kinda sucks. Sometimes I can't even take down the small green gargoyles with fist altfire and I think I should be able to reliable oneshot imps with fist altfire. Crossbow have similar problem but since I use it mostly as ultimate kiting weapon where I run around packs of monsters and shoot through the crowd to hit as many as possible at once, it's not that noticable.
I hardly used the fire gloves spell because aiming it was really annoying. I tried to use it at the monastery to cover the plaforms with monsters with fire but I was hitting either wall or even ceiling. Also I think the spread is not that great and the cannon have higher damage output in the same situation.
The infusion scrolls would really use some UI counter. Their effect is not that visible specially when you are shooting on something far away. Infused weapons have some problems with weapon switching by using mouse wheel (next/preview weapon).
Lot of cliffs and platforms you are supposed to climb are badly visible. Especially in dim caves. Outside it's fine, when you are using the grass top platforms they are absolutelly perfect, but through the side cavers I often had to open map just to see where to go and finally found that there are stairs in the room.
And few bugs: