Double players (optional, some players can play separately and have different advantages, and vis versa)
Custom karts
Bob-OMB karts at the end of balloon battles
Tricks + bikes (not over powered to karts like in MKWII, and, once again, different advantages)
More retro and nitro tracks ( I know this is heaps, but 64? It is the number of N64 and the Wii U will be rather powerful, and HD)
My ideas:
More characters, heaps
![:D](http://s.thewiiu.com/public/style_emoticons/default/biggrin.png)
Plus customizable characters, eg. T-shirts, pants etc.
Make your own track, ninty, if mod nation can do this, MKU can D:
Weather, it'd be awesome to race a luigi circuit at night, or snowy, rainy etc. ( this would be AWESOME for online )
An amazing online (obviously!)
And finally, of course, epic HD
![:D](http://s.thewiiu.com/public/style_emoticons/default/biggrin.png)
Tell me what you think and if you have anymore ideas
![:)](http://s.thewiiu.com/public/style_emoticons/default/smile.png)