I'm hoping it will be, but how much is Nintendo gonna have to fix via firmware? How many patches can they actually release?
About the controls, it's more comfortable to use B and Y, that's simple and stated and fact. Also, Nintendo made the stupid decision to use B and A, something they even didn't stick w/ when using SNES games. The thing about it is though, if you use your Wiimote, then you're not gonna have to worry about B and A being hard to use on the Classic controller. The problem here lies in the fact that the Classic controller is a lot more comfortable to use than the Wiimote. The only reason you can even use the Wiimote is because people don't wanna spend another $20 on another controller that won't even add much functionality if all they're gonna buy is NES games. But the thing is, if they did buy it, they've be highly disappointed.
Just to add something extra:
For anyone that doesn't know this, Super Mario Bros. was actually designed to be played with arcade sticks, and I own some myself. Lemme tell you, the benefit for being able to use GCN controls makes it so my GCN adapters for my arcade sticks will work w/ VC games and man is it fun using the arcade sticks to play those games. It just gives them a whole new dimention, a new feeling. It does take a bit to get used to the feeling of arcade sticks, but after that, you should be good. The sticks I own are the X-Arcade
Solo and
Dual and the Quasimoto
QuasiCON 2P