Also, Cat Peach
I’m still miffed that the costumes in Super Mario Maker only work in their 8-bit renditions, but you have to give it to Nintendo for adding so many to the game. Next up on the block is Cat Mario and Cat Peach, which can be unlocked by playing their respective courses in event mode.
The checkpoint update was a step in the right direction, and I hope they continue to add more missing features to the game, like slopes.