Tried out your demo. Some feedback:
The controls are smooth. The models and animations feel good.
As the dotplus mentioned, arrow keys + mouse is awkward to play for most people. In fact, the first thing I did was to rebind it. In unity you can enter the multiple bindings for the same action. I recommend binding movement to WASD/IJKL etc. common combos so that people can play quickly regardless of their keyboard.
The camera is definitely hard to get used to. It had a tendency to snap to either the top of the character or below it. The former makes it impossible to know where you are going/see nearby platforms. When it's below the character, it clips through the ground and is even harder to see. As I haven't worked extensively in 3rd person games, I can't give too much suggestions but you could try separating y axis sensitivity(and decreasing it) and clamping the angles. There are a lot of GDC talks on platformer cameras so you could try researching that.