I loved the harp sounds when you pressed correctly! Hmm... I feel like visual cues are not as easy to follow as audio cues (which is why music/rhythm games have a soundtrack you're trying to follow), so I might've been a bit more lenient on the timing.
I also felt like the alternating between two colors was a really cool idea, but it only appeared fairly late in the game (10th level, after which i got stuck), I think it'd be fun to introduce it earlier. Visually the game is very fun, with the people jumping around at the beat, and the audio is a really nice feedback. The game also felt nice to control. Great job!