Interesting concept! We also did a rhythm game and its interesting to see the different interpretation. Yours is more faithful to the "countdown" theme. The vibe is really fun - similar to being at an amusement park. Movement feels nice. My main gripe I suppose is that the beat is in fact on the OFF beat (i.e. the & of 1 & 2 & 3 & 4 &), which makes it a bit harder and not feel as nice IMO.