Being that I really like the price point of games and the system itself, I'm going to be careful to suggest things that I believe would not have dramatically impacted the price of the console ...
First off, I would have liked 1 to 2GB of flash memory rather than the 512MB it currently has.
I would have liked the Wii to have an improved GPU to produce as high quality (per pixel) graphics at 720p and 1080i; I could care less if it had the ability to handle the higher quality texture effects that drive up development costs on the PS3 or XBox 360.
I would have liked a per profile friend code, with the possibility of multiple profiles per system, rather than the per game friend code.
I would have liked the Miis to be a much more varied set of avatars, and for Nintendo to have created the tools necessary for indie developers to create their own Mii games that are downloadable via Wii Ware (obviously, with an insanely high bar for quality on these games).
Beyond that I don't really care.
