loads of things have been suggested from restricting the engine size of cars that can be driven by young people, increasing the age when you can get a license, and having no night driving for the first year,,,Would suggest restricting engine size would simply encourage manufacturers to increase HP by reducing weight, Not allowing drivers under 21 to carry passengers would allow them to drive to and from work but would create problems for families...I suspect only an increase in the age limit would have any effect....how about 60 for all and you get a free old person hat when you pass your test