I think they should raise the speed limit on suitable motorways to 130 or 140.
Modern cars can drive that speed without effort, if theres three or four lanes, 'fast' lane is for over 120kph only.
Local streets on the other hand, 50kph is fine. Lack of attention and/or impatience is the killer there.
More fatal accidents in lower speed zones, kids on bikes and skateboards going out in front of cars.
The higher speed accidents get the headlines as they tend to be more spectacular and devastating.