I think to do this right (safely) we need to start looking at how to integrate roads with self driving cars and trucks and at vehicle to vehicle communication.
At some point there needs to be standards set for these kinds of things and, really, the sooner the better.
I think we, as consumers, would be better served with a vehicle that could safely drive down the highway for long distances right now than a car that can drive us to work and back on city streets 10 years from now.
And if we integrate roadway to vehicle communication from the highways outward the transition will be more efficient, especially for trucks.