I understand your point, but everyone seems to be forgetting the moon in all this and also that thing called 'artistic licence'.
The strong rim-lighting created by the phong is from the headlights, the rest is from another lamp placed off-screen, much darker and bluer, acting as the moon. "But why is it so strong on the guy?" I hear you ask. That's why I mentioned artistic license - if the whole picture was equally dark, or if the whole picture was brightened more, then there would be very little focus, especially considering there isn't much depth-of-field either. Think of a night-scene in an action film or war movie or whatever; quite often the main character is really brightly lit and everything else very dark. You don't notice it though because your mind says "this scene is dark and blue so therefore it is night" and you are simply happy you can see the character and what is going on. The same concept applies here, although the lighting contrast is not quite so prominent.
Even though, the light from the moon wouldn't be as lit ;)
It's great overall, but if there was a moon, I would have had it to shine down from another direction, then the same direction as the headlights.
I know what you are trying to imply, but the light is way to bright :P