After playing your game to which it's challenging, but fun platform that reminds me of Kirby and Sonic. May I suggest is to zoom out the camera to capture the entire level. That way the player will have a better feel to the game and know what to expect. Next is to add in game play of collecting items like a map that display the HUD of the level or a key to find and unlock the door to the next level. Finally, add a different enemy as obstacle to enhance the challenge of a level. I hope this suggestion would help improve your game.