I totally agree that Protect and Shell are too short but the Spikes in my opinion are perfectly fine duration, if not better then I expected.

As for AoE, yeah and no. I suppose what Ranka has said and same with Casting Time.

Cancelling needs to be improved but it is there (as people already pointed out). A nice hotkey or something like Esc or a controller button, would be cool if they added it.