This is where the failsafe tech from auto driving vehicles should come in. All freight vehicles etc should have a system in place that brakes in you are coming up on someone and that holds you in your lane etc. We will probably see a switch over to more automated vehicles in the next 10 years or so and it cant come fast enough. There will be lots of hold outs with older vehicles but they need to be penalized harshly if they use their phone etc.
A lot of vehicles have that as standard now, I know my car from 2007 has it and the Mercedes I rented on holiday had it too. On my car it is switchable with the cruise control and you can alter the distance it keeps you from other cars, it can operate without the cruise control too and sounds a warning if you get too close to anything, the one time it would be really useful is in the snow, but the snow blocks the radar pulse and so it doesn't work, it does work well in fog however.
The cruise control is a little different than all the other cars I have had in that if you set a speed and are going down hill say it will put on the brakes to keep you at the set speed, all the other cars that I've had that had cruise control it was more like you set a speed and that was the minimum it tried to keep the car at.
The park brake, if you pull it on at speed then it will uses the normal brakes with the ABS to stop you as quickly and as straight as it can and only once your speed is less than 5mph does the park brake come on, so handbrake turns are out the question
The other thing about the Merc I had on rental was that there was no owners handbook, it was all done through the navigation/multimedia screen, the car had internet connection as standard and an iPhone app to help you control it, there was quite a learning curve on the controls of the car, from the engine modes to suspension set up, by the time I handed it back I was getting comfortable with it.