Thanks for the spirit!
- I'd try to make the UI color palette (icons, text, squares...) more consistent with the main colors of the game (those blue, red, green and yellow of the game). This tool helps a lot ⇒ http://colormind.io/
- The stage number ("3/9") takes a very important place on the screen, while is not as important info while the player is playing.
- The icons at the top, while they're pretty clear, look pretty standard and dull to me. Again, they're clear, and that is crucial.
Let me know if you agree. I'm not an expert either, but tell me if you need help with anything.