In the end, good software design is the most important thing with a gaming console. I know there is a growing disagreement with that mindset with all of the multipurpose gadgets we have nowadays.
The control scheme itself, whether it be standard controller, mouse and keyboard, or Wii remote, cannot by itself dictate the quality of a game.
Great games can be designed around all the existing schemes.
Well designed Software is the reason the DS is where it is, and you could argue that in comparison with the PSP, its merely GBA+ in power. Hell, a ton of DS games visually appear to be on par with GBA stuff.