I think that this version of MArio Kart should have some changes.
Firstly, it MUST be Web-capable for Multiplayer. There shouuld be a bot option. They should have Rainbow Road again (Sans railings except on tough turns) Long tracks and LOTS of them. More than 4 battle arenas, at least 10, downloading them off of the web possibly. An arena creator would be cool, as would be a track creator.
Anything else that you'd like to see? What are your expectations? What do you think would be a cool multiplayer level. Describe it.