A couple more comments that come to mind:
Some of the autocross cars have wheel rates over 600 pounds per inch! The tire has a rate of approximately 1000 pounds per inch, so these cars are essentially oversized karts.
Before the ground effects cars were banned from Trans Am racing, it's my understanding that the constructors were considering simply doing away with the suspension springs.
We've all driven karts, at one time or another, and we didn't miss the suspension on a smooth kart track. But, driving or riding on city streets is another matter! I remember, back in the fifties, getting a ride into work with another Chrysler engineer. His car was an Elva http://www.elva.com/elva-history.html
. Appreciated the way it handled, but my tailbone was glad to reach the parking lot!