"What Mario games are more similar to 3D World?"
The 2D ones.
The co-op focus ruined the single player aspect of this game.
The forced isometric view, from the side.... means even if its rendered in 3D, it plays alot like a 2D game in sections.
Its a rather dissapointing 3D mario game.
Is it a bad game? no, but its not a great game, and it falls below what you expect from a mario game.
Its a shame to even compair this mario game to the greatness that is Mario Galaxy.