Absolutely. It would be great to create our own events, define it's rules, the tracks it would use... that's is something I've been wishing to have in GT for a long time.
I never thought of it. Now that you brought it up, it would be awesome! They should definitely have a race editor in GT4. That would be so fun to make up your own races, rules, what cars will be in it, and tracks raced on!
That would be the best way to improve your driving skills as well. It would be like Run & Setting, except with other cars to compete against your newly tuned car.
i love that idea, but it would be much better in Arcade mode because if it was in Simulation mode, you could make it so easy that you could beat the game within a week or so, but it's definitely a great idea.