Multiplayer would be great to have! Other than that, this game is perfect! Such fun to play! ^^Great work! I love the sprites! :)
Also a common collectible such as coins would be nice! Even if they dont so much. Powerups would be cool too. But above all else, i def think the game would benefit from local multiplayer the most. ^
A coin mode would be nice, maybe something to use in maker mode as an alt win condition... but maybe in regular play it can be used to buy more skins.