I do a lot of highway driving and in the night too, most free highways are dark where I live - so its priority one to make sure I can actually see the damned road.
I make sure that the headlamps are aimed perfectly correct (lights should have correct cut off and correct flick up on the passenger side to illuminate road signs.
I also make sure the bulbs are not worn out
I make sure the windscreen is crystal clear - no fogging or coating - never use the same cloth to clean the car metal body finish and glass and use a streak free cleaner (water + alcohol mix is best)
HIDs are 10000% useless in halogen reflector housings as they only become a ball of light that illuminate 5 ft of road ahead of your car - dont think that bright equals vision.