I always liked this world. Thematically, it was just really cool to go from the "ground" section up to the sky to finish it off. And the shoe! I wish we got more of that in the game.
Yeah, I wish this game would've done more with Goomba's Shoe, but it's only exclusive to one world. Not counting its return in Mario Maker, this is one of those power-ups that's been slept on a lot.