I really dare you to create some method for minus button. I personally would love to use GC controller with my Wii U games and Wii games such as Monster Hunter. Many games really need the minus.
I would definitely buy at least one adapter and if there ever was going to be any competitive scene for SSBWiiU I'm sure every Smasher will. If it functions near flawlessly with no noticeable input lag and has the analog shoulder feature this thing should spread like a wildfire among not only...