Imagine how fun that'd be? Mario maker on the WiiU uses the the "New Super Mario Bros" Engine for each version of the game.
Making a more old school styled game (and more basic) would be super fun!
There's the Yuusha Maker made by a Japanese (key B35443A4). Remember, SmileBASIC server bans copyrighted stuff, so any flat-out Mario Maker clone keys will be deleted.