Over fifty years ago I started building dual head lights on my bikes, along with dual spots. One thing I’d always noticed about singles is that other oncoming drivers took the single light to be a car with a light out and then started guessing about which one it was. Putting more light out front also helped light up the other guy which gave me another edge. I worked at night occasionally so I rigged for it.
I saw a rider the other day that had a brake light on his helmet. I thought that was an interesting idea.