Huh ok, making the lane/pad flash differently depending on your accuracy is a good idea. The reason I didn't add an accuracy meter is because when I play these sorts of games I don't ever pay any attention to it whatsoever - also as this was made quickly for a jam, I think any perceived inaccuracy is more likely to be my fault in terms of level design, rather than yours in terms of timing.
Using a more central control scheme is a great idea, though I intend to make this game multiplayer in which case you'd want to spread the controls to the sides - but seeing as it's not currently multiplayer, I agree that would have made more sense! ZXC turned out to be a bad choice regionally as well, as some people have a Z somewhere else on the keyboard - I'll just make the controls rebindable and then it doesn't matter :)
I agree that the backgrounds could use some more going on - but I didn't want to make it too distracting! There is actually motion though, in the falling cars, the indicator lights of the cars are flashing, and in jazzy beat, the speakers are animated, and the lady on the left taps her hand (these animations activate when you press the controls).
But if you felt like it needed more, that's good feedback, it means I didn't over do it. I can always add more! Though I think I will then need to add some kind of 'disable animations' at that point.
Thanks for the detailed feedback, was there anything else as well? :)