This idea is just very badly thought out. Theres elements that could be put into practice, but you only have to look at whats going on in America to see how impractical a law like this would be.
I was over in the states for a while a couple of years back and different states have different variations on this.
Some states say that you cannot drive a car after dark at all if you are under 18 unless it is for the purposes of work or school/college.
Some states say that you can drive a car after dark but without passengers under a certain age, and several states let you drive a car at 15 I believe.....
Basically all this means that nobody knows what the hell is going on because these laws are so difficult to enforce. Even the police there find it difficult. Whenever you try to regulate when and how someone can drive, you just end up with a lot of confusion.
I think the only way you can regulate how inexperienced (and I'm not just talking about young drivers here) drive is to get rid of the driving test completley and introduce a modular assessment course done by DSA approved instructors. This would hopefully get rid of the element of drivers who drive sensibly on their driving test and like idiots afterwards.
There could perhaps be courses at a restricted basic level course (perhaps with limits on experience (not age!) and limits on the types of cars that could be driven) and then an intermediate and advanced level, which could only be taken after certain experience requirements had been met and would allow you to drive more highly powered cars.
I don't think that the time of day someone drives at, their age, or the number of passengers someone has is relavent so long as there is training in these areas. I hate this idea that just because some testosterone-filled 17 year olds arse about on the roads then all people under a certain age have to pay for that.