Great idea. This could in all honesty replace any driving (car and bike) and aero tutorial.
It could be a relatively small race track , a few different drivers with their own style and skill and the player, perma locked in a vehicle. You could even have different cars with different parts on it. If you pay more flash , you get a better vehicle. (Call it micro transactions). Maybe, just maybe, ramming could be implemented inside the simulator. It could provide good data for crashing and ramming. New players can learn how vehicles handle and the races from red and gold can show how ace they are. With the people from gold being able to pay to win.
The simulator could have a small tutorial (start vehicle , drive command , accelerate command , decelerate , shutdown.) built into it, thus allowing players to learn by doing instead of learn by reading. Make It small tutorial depending on the vehicle (car , bike , aero) you are driving and you are good to go.
I would however make it a single player only sim. I know , from an IC perspective , it would be greater to have it multiplayer. But having a race course where you don’t have any negative effect from crashing your car would destroy anybody’s chance from making an in game , outside of simulator racing event. There would be no reason for players to try to organize a racing event with their own cars if you can just race in the simulator and not have to pay for crashing the car. Same thing how a large part of the dome population was doing combat training in the sims instead of in real life. Not that this is a good or bad thing , but the UMC fights would probably lose appeal if done in the sims.