Quinn R
Quinn R should probably have an in-combat cooldown. It was intended to make Quinn essentially a QRF (Quick Response/Reaction Force), allowing her to do a lot of different tasks in a lot of different places. I don't think it was intended to give her unbeatable chasing potential. As it is, if anyone is low after a fight, Quinn just toggles on her ult and mows them down, especially since her Q is an execute.
Might be a good idea to give her R a cooldown that refreshes every time a champion hits her, maybe something like 5s. That way, she can't instantly chase you down after a skirmish, but she retains her QRF identity.