I love the art individually, once thing that is getting in the way however is the sun in your background. Since the camera keeps the player centered in the stage, when you jump the player is then in front of the sun and the colors make the character hard to see. The enemy placement was good and lined up with areas you naturally want to go, so it makes you slow down a bit to make sure you don't land at the wrong time and get hit. Otherwise, everything seems to work great!