We have no idea how they'll angle the controller. It may be only able to stream games at home, but we don't know what you can do with it when you take it outside the home. Small downloadable games playing, movies, web browsing, etc. when you're in range of Wi-Fi. Besides that, I don't think the controller will be more than $70.That's not too expensive and crazy.
Besides all that a touchscreen plus traditional controls gives Cafe a surprising breadth of control options. This system will be able to play almost anything, even traditionally PC-only genres like complex strategy games and MMOs with little UI reworking. And also, a screen in a controller just gets me giddy thinking of everything that will be possible.