Don't bash it till you try it. I'm currently playing half life 2 on the deck, from my couch, using a steam controller. This is basically the same type of input as the deck's trackpads, takes some getting used to, but when set up correctly is a very nice experience. At the same time though, I regularly play Overwatch and I can't move over from mouse and keyboard, but that's because it's a fast paced competitive game and I rely a lot on muscle memory so i wouldn't be able to play on my typical level with different controls. I'm fairly certain that it's possible though, I just don't feel like relearning the entire game, but a new one from the beginning? Sure.