I think I'd have to go with SMW
They're interesting but aren't used in novel ways. Leaf is great and Cape expands on it. Frog is entirely optional, Tanooki and Hammer are nice upgrades to Leaf and Fire Flower but don't meaningfully change how you approach the game, the Shoe exists for a single level gimmick, and the map items are all little shortcuts to play less of the game. SMB3 does not use its unique tools to build new kinds of puzzles or present alternate paths through a level they just make the challenges a little easier.
Cape, P-Balloon, and Yoshi are much better utilized.