I really think there must be a stage based on Kirby's Epic Yarn. It's a console game, it's kinda obvious, and it can have its own gimmicks and unique style! Other stages... well one based on Duck Hunt, maybe something for ROB, I think Magicant will be shared between versions cause its just too good...hmm...
But yeah! Lot more hope for this version regarding stages. I think every franchise will have at least one, maybe not ROB unless they have a stack-up stage or somethin. Brawl had 41 if I remember correctly, so I think the Wii U version will have...maybe 50, 10 being past stages, maybe 7 Brawl, 2 Melee, and a 64 stage remastered? And also Stage Builder with more options.
I just hope to see more Wii U stages and stage builder in a pic of the day! Maybe not soon, maybe after October 3rd, but eventually.