At the time I took the picture, just after assembly, I was going for a ride in the daylight and transporting nothing on the rack. The light was there for a visual clue to approaching automotive drivers, i.e. it was there for safety reasons and not illumination for after sunset riding.

In the long term I plan to make a leather bag for the rack and mount an appropriate light to the eyelet at the bottom front of the rack. The light will then be located between the fender and the rack and will be unobstructed. Hopefully it will appeal to your sense of style and practicality.