Not much.Maybe a few different colors for the Power-ups.Too much red and Green.That's my only hang-up.Love the music too.It is overall a well crafted game.
I wouldn't change anything else.
I guess a 3,2,1 go would be cool too!
The music is from Kevin MacLeod (incompetech.com)
Red/Green: Ok, I'm still thinking about the color scheme in general, also how it changes with the difficulty over time (right now only the track border color changes, I have sky and ambient color changes ready as well, just no satisfying color combinations yet.)
Red/Green might also be an issue for people with color-blindness, maybe I'll look a bit more into different color palette there.
Good input, thanks.