My first car wouldn't go over 70 even without government-imposed restrictions. Actually, that was a speed hazard, too, because I couldn't accelerate fast enough to maneuver through traffic (car went from 0 to 60 in about three days. More if I had to run the fan on a hot day).

How about better driver education and better enforcement of existing speed laws? Around here, the police speed worse than anyone and I see people do all sorts of idiotic things on the freeway without getting ticketed. Fine the pants off them and boot the car until something sinks in.