I would love to see a fully realised 3D HD mushroom kingdom. Big castles, strange worlds. A massive sewer system with water flowing around. Open world would be cool.
I would also love if they completely changed up the formula, just not in a sunshine way. No waterguns, no vacation. Got to be various powerups, and a standard mission, though peach doesn't need to be captured. She could be playable.
I think true multiplayer in visually stunning worlds would be enough to wow people.








