Touchscreen controls are a terrible "solution." Latching your phone onto a large controller is better at least, but I still can't see a casual gamer doing that. It's kinda like carrying around a 32" TV in the back of your car in case you get the chance to hook it up somewhere and plug in your game console.
Again, I'm not trying to be combative or argumentative. I just believe touch screen controls are not a solution, and I don't think that people will carry around a full sized controller to game on their phones or tablets. That's because the controller is so large. Without a controller these games have no portability.
Asking us to accept latency and suspend disbelief about internet connection worries is one thing, but asking us to use TOUCH CONTROLS is a whole different ballgame. We are regressing to before NES levels of bad gaming here.