I voted No, purely down to the fact that I think the AI is already a massive leap forward from GT5. I mean, never has a GT game's AI actually tried to race and battle with me after I took their place. I'm loving the AI to bits.
WRONG !
They don't race you, they drive the first lap (or 2/3 on longer races) on their own pace (wich is not slow at all) but then slow down till you catch and overtake them, after that they start going faster again.
You can see it on the split times or when you watch a replay and change to the leaders car.
(Do the Mazda Roadster race in nat.A with 8 laps with the stock 3rd gen.MX5, first few laps they do 1:11s and you would have no chance to get them, but then they slow down to 1:16ish till you get them, then they strart doing 1:11's again)
A AI slider can't fix that, the races ar simply to short to be fair on equal cars and starting last.
But instead of just making the races longer, let you qualify for a better position, or give you fewer opponents, or not always let the opponents with the best cars start first while the others with slow cars park in your way on race line some genius at PD decided to rewrite the AI to gift you every race.
Taking a slower cars does not really help because it only makes them slow down even more, up to a point where it gets silly.
For me this ruins the game, i see no sense in doing races i cant loose no matter how i drive, it is against all rules of sportsmenship/competition.
Best solution would be back to old AI and make the number of laps adjustable (or double/triple them)
Then you could adjust the difficulty with your car.