I have played four characters to level 40 or so. The biggest issue for me was the animations. Loot just appearing on the ground, attack and spell animations, and monster animations all reduced immersion which made it harder to continue playing. If all of those were smoother and more believable it would help a lot for me.
Aside from that and crashes to desktop, everything else seemed very good to me. I like the skill system, passive system, defenses, and loot. I still don’t quite see how DOT’s will scale well enough but I didn’t experiment with them very much.
PS. Please change adaptive spell damage to just spell damage. Adaptive is a name only a programmer could love