Yeah, smashville is awesome for MK.I am convinced Smashville is his best neutral, unless Delfino is a neutral at your tourney.
Luigi's is a fine stage for MK even against Snake/Olimar/others who abuse it.
Japes is fine vs Falco.
As for mansion, I think it's pretty overrated for MK. Nado works well there, but that's pretty much it. when playing someone that knows how to camp well on that stage, MK gets gayed hard.