Help design a better bike light

I'm not a designer or entrepreneur so I'd never bother trying to make a new product like this but I have often wondered about the merit of a light that attaches to the top of your top tube near the head tube or indeed on the back of the handlebars with a wide light source surface area that emits a lowish power fill light that actually illuminates the body of the rider.
I often see riders on dark bikes and in dark clothing with a regular front light and they seem almost invisible apart from a spot of white light approaching.
This could go some way to countering that without the need for all the pro-commuter vest and helmet lights.
Would still need to be used in conjunction with regular lights.