Regarding music it is always a thing of liking or not. The main thing when creating a game like this: You need to like it! For me the BG is not the best here, I guess. It is not cartoonish, but just house style (?). It would elevate the experience if it is a music that is connected with "competition". Fast and cartoonish, yes....
But I think SFX is even more important here. Some more fancy sound effects when hitting a platform, falling down etc.