To state the possibly obvious, amusement ride control systems should have redundant, fail safe safety systems. Each and every accident should be investigated with involvement from both the park and the manufacturer if there is any suggestion of mechanical failure. Finally, the manufacturer should forward any lessons learned to the other operators of it's rides. This doesn't require Federal legislation, just good sense considering the possibile liability.
What is outside Markey's legislation, and I never hear mentioned on coaster web sites is the need for parks and manufacturers to investigate and communicate "near misses". A "near miss" is an incident or finding which results in no injury, but the portntially could have. If park "A" finds a cracked axle on a ride, it is important that the manufacturer and other parks know to look for the same defect.
That said, I'm going to repeat, "No one has died in an accident on an amusement park ride in the United States in 2001. The only person who died in 2000, died because of his own gross misconduct." This is an excellent safety record that almost any industry can envy.