Charming as absolute heck, crammed with memorable moments, and 'aha!' gameplay mechanics.

I'm definitely in the camp that wishes a few of said mechanics were expanded upon more. The rapid fire nature of the games changing abilities and level structures keeps it super breezy but also can feel skin-deep at some points. You can give Mario a grappling hook in this game, and I don't think they made a big enough deal out of it.