This is actually in response to danpollard
I had the entire message quoted, but it was quite huge.
1) I don't know about pissin' off the manufacturers. I sort of doubt that would fly. I'm surprised to not see Volvo in there though - doesn't Ford own them now? You would have thought that Ford would green light the project for all their divisions. (Maybe not Land Rover...)
2) I don't care about the detail of the pit lane (if you were referring to graphically) - however, the ability to make some limited setting changes would be nice - downforce and such.
3) Tire marks - <shrug> While it is fun to supe up a Cobra, put sim tires on it and do burn outs, I'm not sure that there'd be a big improvement from doing so. (but it is a riot) lol
4) Used cars and Racing Mods - For sure... hehehe - And, better yet, if manufacturers would ever agree to show damage, you could even buy a complete beater - rust, dings...

No real point to this, it would just add more realism - Hey, if you've got a lot of rusted through spots on your car, it's lighter - less sheet metal <pointing to the rusted out Hyundai Excel in the parking lot> It's a speed demon.
5) Winning the same care many o' times - The biggest problem with this is, it becomes too easy to make $$. There wasn't nearly as much of a challenge in GT2 when you could run just one single race (if I remember correctly) and win a car. The only way to combat that is, the first car you win is worth X, and subsequent wins decrease in value by 75% or some number they come up with.
6) Date schedule - Hmmm... This would add to the "sim-iness" (that's a new word I just made up) of it but wouldn't improve the gameplay (atleast in any way I can figure). I wouldn't particularily care.
7) Tire blow outs - for sure - This would keep you honest in the endurance races - no more "drive with your tires red indefinately"
8) Flags - Ahh... I'm not sold on it - but I s'pose I don't need to be. Pardon my ignorance, but isn't it pretty much just Nascar that uses the flags? Does the GT Series? (I just started getting into watchin' the GT races when Speedvision/channel changed to the Nascar channel). From what I've seen, if you spin your car, everyone else just does whatever possible to avoid 'em.
9) Spins - Yes, spinning should be more prevalent... One thing - and I dunno how possible this would be - If the PS2 is bright enough to know if you hammer someone on purpose, with the sole intention of spinnin' them should a) disqualify you from the race or b) fine you. (or both). Spins should happen by accident, but not intentionally.
10) Car maintenance wouldn't be a factor unless the manufacturers agree to allow damage.