I honestly think even good bad Nintendo games should have SOME rep.
Urban Champion while not being amazing. Was pretty silly. I don't think it should be a scrolling stage. But a static one. Where it's walk-off, but every level of the windows has platforms as windowsills and whatnot. With the people in the rooms dropping flower pots... and police coming by where everyone has to stop moving or taunt (Like the Wario Ware stage) to act like nothing is going on. And when someone gets a K.O..... CONFETTI! LOTS OF CONFETTI. THE ONLY REASON FOR THIS STAGE IS THE CONFETTI.
*Ahem* Anyway. Those are my ideas. I think while it could definitely not be a good Neutral stage, I think it could ABSOLUTELY be a great "For Fun" kind of stage. There's so much potential.
And as Staypuft said. Spiking or walking onto a manhole = insta death.
It has potential to be quite the interesting choice.