Very fun! Though I didn't get much challenge until the end since I've played it once before. I played with a controller and it worked great*, though the tutorial prompts should probably change depending on whether you use keyboard or controller. The visuals are polished and are entertaining to look at. The music and SFX fit well. One thing I'll mention is the lack of purpose to displaying the amount of flag levels beaten / total in the top right of the map, given the worlds are basically linear. I would suggest removing it as a pointless UI, unless you plan on allowing some non-linear chapter completion or something.
Good job, I look forward to more of the game.
*For some reason the reset action was set to 'disconnected' surrounded with <>(or some other bracket) when I selected the controller option in the drop down menu. Don't know if it would have worked or not since I changed it before playing the game.