I'd also like to see some sort of cooldown (probably not the full cooldown) on cancelled skills (particularly teleports) because it doesn't make sense for someone to be able to fake-cast stuff for free, and because interrupts give the cooldown.
Well, I think it does - interupting is a counter to just teleporting out of a situation and never dying, and the like. If the interupt didn't activate the cooldown, what would stop the person from just re-using whatever ability they wanted again, safe in knowledge your interupte is on it's own cooldown? Fake-casting, as I like to do with consumables, rewards the player for a little fore-thought and planning.