I've been playing Twitch this free week and his damage is too high imo. I'm not very good with him yet but I win some exchanges just based on how much damage he can do. Usually able to get a kill at level two and four if my support is decent. His ultimate is satisfying as hell if you get a good one off but I think that is actually fairly balanced. I just think his E gives too much damage compared to what other ADCs have. Nothing in the game feels as good as Expunging a fleeing enemy or getting a multi-kill with it, though.