I'd rather suggest to scale the difficulty by crippling the AI on the first stages instead of making the car easier to drive. Otherwise you force the player to learn to drive twice, first with the aid and then without it. Aid should be in the options and turned off by default. Maybe if someone fails miserably a couple of times in a row, there could be a message hinting that one can turn the aid on in the options. But then on later stages or difficulty levels I would make winning with the aid on impossible (because you need to do some crazy drift or something).
I remember that at first RC1 was completely useless, I can't remember what kept me trying, but then with time I was getting better and better and that's what makes you full of joy - that after some time you are able to consistently win something this extreme even on Expert difficulty (ok, maybe except Park Life). If there was driving aid I guess there would be less risk that I'd drop the game after first few hopeless drives, but then it surely wouldn't be a cult classic that I come back to after all these years - I'd forget it after few months at most.