Room for improvement.

Super Mario Maker is an awesome game, but I feel some things could be added. 1st, more power ups (like the Frog and Hammer Bros. suits). 2nd, have Keys to unlock stuff with. 3rd, Checkpoints. And that's about all I can think of right now, but if I come up with more, I'll let you know. Of course these are just minor things, Super Mario Maker is still an awesome game worth playing.