In the terms of challenge, it remains me a slightly different idea of Seasonal Event. How about the format change back to normal race (start at 7th), but it forces you to use a much lower PP and tougher tire choice against the much higher PP and much better tires AI?
I think such idea will at least eliminated the chasing rabbit race format, and it require much more challenge for the player as the tire selection always not too tough in the Seasonal Event.
Changing the player's starting position or the maximum PP or tire grade would have absolutely zero effect on the races being "chase the rabbit." It might provide some variety to the specific experience but you'll still have one overpowered car - usually starting at or near the front - that you have to chase down while blowing past all the other irrelevant cars to get to them. The only difference would be the distance to the rabbit, the number of irrelevant cars in between you and the rabbit or the performance gap between your car and the rabbit's.
A little variety to the scenario might be nice, absolutely. Starting from the back makes the backmarkers
slightly less irrelevant however, as there is largely no reason for them even to be on the track if you start from in front of them(unless you screw up or the rabbit starts at the back). And of course people already complain about the fastest AI cars occasionally being 5-10 PP above the limit despite the fact that having the AI driving a car is basically worth -40PP or so anyway and in most cases the player is running well below the limit for a good
race challenge or greater rewards. So forcing the player to be in even more inferior equipment won't make those people any happier.
The only way to eliminate the "chase the rabbit" effect is to make the cars all roughly equal in lap time. And of course with the AI's inablity to drive at a proper speed, the player is still required to use a detuned car or lower-grade tires to create a satisfying
race challenge as seen in any one-make event in the game, from one-make practice events to the Gallardo race(which most people mistakenly believe is against stock Gallardos) to the NASCAR event(Daytona's difficulty is a separate case) or the Formula Car events(difficult for some, but not because of the opponents).
There's no way around this that I can see except to make the AI faster and more competent and then scalable to the player's preferred difficulty, and after 15 years it seems unlikely PD is very interested in doing those things.