circles

Very nice picture. The only suggestion I have is to attempt this with more traffic and a longer exposure - I am picturing a shot in which you will get a complete swirl of light trails. Since the light-trail would be very prominent in that case, it may also help to elevate the camera position a little, to separate the globe from the swirl of light.

However, that is only a suggestion for a different take on this. It is still a very creative picture as it is!