Only two buttons?
Oooooo!
This screams illuminated jumbo domes!!!!
(well at least to me...)
Sounds cool, though i'm not a big fan of dancing games...
I have a tiny suggestion, though...
If you're going for a dancing cab, why not also incorporate an EYE-TOY?
You could 'hide' it somehow, then it will be really neat...
And i'll say again, ILLUMINATED JUMBO DOME!!! You have to put one!!! (or two

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