The pole style, where there's one pole that arcs over the road and has 2 lights on it, would be best IMO.
It would have to be heavy, and the lights light, to stand there.
Or, it would need just a long base that runs out under the lights. Textured to match the roads, or even transparent.
It would be less likely to be hit very often.
A wire across the board would look great, but would be hit or snagged on a pretty regular basis I would think.