That sounds nice!I would love to see a stage based on the Eggman Fleet from Sonic Heroes. Canons would be locking on to you (that would prevent camping), some robots start attacking you, and a fem cameos in the background (Team Dark or Team Chaotix destroying some battleships) It would be a very high tension stage.
I was thinking of something that shows the Biolizard fighting Shadow in the background, and the stage would keep changing (Like, the battle starts in the arc, then the Biolizard transforms into Final Hazard and shoots up into space, while Shadow turns into Super Shadow and goes after him, then you shoot up and land on a platform in space while watching them fight once more) then Shadow would use Chaos Control and make the stage start all over again.