Idea for a rather unique champion passive

I'm thinking either a Top lane Brawler that wields a melee weapon or just his/her fist, or a marksman that throws their weapon.

Passive : Auto attacks canceled by movement commands still occur, inflicting a portion of the damage that a normal auto attack would that would depend on how early/late the attack was canceled. Auto attacks that trigger this passive cannot crit nor apply on-hit effects.

Thoughts on it: I think it is certainly unique as canceling auto attacks is one of the few things not touched by a champion ability (unless you count kalista's, but sense it merely states that you can't cancel an auto attack, I wouldn't). As for why I would choose a Brawler or a champion that throws their weapon? Well it just makes sense to me. Everytime you play Sion you see him take this gigantic oversized swing at the target with his axe (or just punches them lol) and I thought it would be cool if you could cancel it to do a portion of the damage to represent an attack that is meant to be fast but not powerful...like a flick of the wrist type motion.