Super Mario Galaxy
A Super Mario Galaxy style in Super Mario Maker 2 would be one of the most fun 3D Mario styles to build in.
Things start to get a little muddy when you get to throwing around star bits.
They could be added to levels as normal collectibles, but then what would you do to throw them. A fireball button is an option, but if you got a fire or ice flower, then that would have to override star bits.
It would make the most sense to map the action to one of the shoulder buttons.
The power-ups in this game are incredibly wacky and unlike any other Mario game.
You can spring, buzz, or haunt your way around a level with the different power-ups. Since Galaxy 2 is so similar, they could even toss in rock Mario and cloud Mario just for good measure.
Nintendo pretty much already has the platforming figured out. There were plenty of 2D platforming sections in the Galaxy games. All that’s left is to let people get their hands on some building tools and go wild.
We need black holes, planets, and launch stars in Super Mario Maker 2. Just seeing how Nintendo would deal with customizing gravity on each planet in a level would be tremendously fun.