You need more power on the helmet. This should be your primary protection. My bacon has been saved innumerable times by shining 1,000 lumens right in the eyes of drivers who only make cursory checks at stop signs.

When you can see head shadows being cast on the back seat of the vehicle, then you have enough firepower.

I used to also run about the same lumens on the bar, but now I am only running a 2W blinky light there. It is pretty bright, and noticable, but the key requirement is the helmet light.

So the headlamp is a Chinese mail-order CREE-based flashlight velcro-strapped to the helmet. Works off of a rechargable 18650 battery - good for about 40 minutes per battery. The blinky works off 2 x AA batteries. The whole setup cost about $40.