For Donkey Kong, I feel the aesthetic value of this stage would be awesome:
[COLLAPSE="Sunset Shore"]
[/COLLAPSE]
Someone made a thread about visual filters, that idea could go great here. They could have it so that all the characters are blacked out, and you only see their clothes, similar to how you can only see DK's Tie and Diddy's Cap and T-Shirt. For Pika it could be his cheeks, you can get creative with some of them, like Kirby and Yoshi you can outline their eyes or something. Or they could just do away with colors all together and replace it with Alt costumes.
As for a more throwback DK stage, I've always wanted to fight here:
[COLLAPSE="TreeTopTown"]
[/COLLAPSE]
Something about this Endor inspired village is just magical. I can't help but feel transported when playing this level in DKC.
I also mentioned in another thread, the best stage for Metal Gear is this one:
http://www.youtube.com/watch?v=Gu6RHbFj7vk
This battle is incredibly memorable and the setting is real nice. I like the Maya Pyramid in the background along with all the green jungle environment. Throwing in the Crysalis also adds a nice contrast between technology and nature. The stage could also fog up from time to time to make fighting a bit more interesting, and they could show the Crysalis flying around chanting its eerie song.
Also, this would be a great excuse to give us Big Boss over Solid Snake.
Anyway, what do you guys think would be a good Earthbound stage? I still haven't played the games yet, but most of the Earthbound stages have been rather underwhelming. Fourside is the only one I liked. New Pork City was just so.... Empty, and Onett too cramped.