Hopefully this means Sega will make a Smash Bros copy with their characters after this since the last 2 Sega stars games were based on a Nintendo series.
Anyways for this game to be as game as it can be I hope the have a Crazy Taxi level with the authentic music(the probably won't want to pay for it though) and traffic. Also have Crazy Taxi drivers as racers.
They also should have Jet Set Radio characters skating with the rocket powered speed up you can use in JSRF constantly. These characters would have the best turning in the game but they would easily get pushed off the track by other vehicles. Maybe they should be able to spray paint their opponents vehicles as they pass.
Skies of Arcadia characters should be in this game. They really should have been in Sega Superstar Tennis so Vyse and Aika could celebrate a team win with that high five/hand shake thing that they do.