Like many posters above, I have ABS at 1, and everything else off. I'll add, though, that I'm using a DS3 with steering sensitivity at 7 (max), almost always use bumper view, always use a manual transmission, and if I had a wheel/pedal set, I might not use ABS at all.
The reason I personally don't use any aids, is not because I'm an elitist, nor is it mainly to give myself a challenge. It's because I prefer the feel of driving without them, and for the most part, they don't make it any easier for me to drive. I agree that TCS does hamper performance, and maybe SRF would help it. But for me, what it comes down to, is that driving aids, either in a video game or in real life, take a level of control away from the driver, and dilute the driving sensations and inputs.
- An automatic takes the gear choice away from me. Although I sometimes choose the wrong gear for a given situation, it's less frustrating than not having the choice at all.
- I find Driving Line very distracting, not to mention ugly and gimmicky.
- Traction Control often reduces engine power at inopportune moments. In many situations, a little bit of wheelspin is faster, not to mention that it's impossible to "steer with the throttle", be it FR, FF, or 4WD. I think TCS is especially excruciating on gravel and snow tracks.
- Skid Recovery Force feels artificial (it is) and "arcadey".
- Active Steering also feels arcadey and fake (it is, too) plus it take control away from the driver in the same way an automatic does.
- Active Stability Management is at least a real product on cars (unlike SRF and AS), but again, I prefer to make my own mistakes, because when I don't make them, it's all the more rewarding. ASM also takes control away from the driver.
- ABS at anything higher than 1 is overkill for me. Even with a DS3, I find few (if any) cars that fully lock-up easily or often. Like with TCS off, it's often beneficial to bring the wheels (especially the rears) close to lock-up in order to "pitch" the car into a corner. I assume a foot pedal would make this even easier to modulate.