I popped over from GameDev. I would recommend adding some type of fanfare when you reach the finish line, like confetti or some celebration to that effect. I would also like to see some type of camera control, unless you think that would make it too easy. In terms of new content, I would say maybe add some parallel parking levels. This would be a harder game mode because you would have less margin for error. You could also make levels with pedestrians where you have to time your movement to avoid hitting them.