Wow, that looks great! 
I love the curve, which looks realistic. I see too many layouts with roads which have 'curves' that are more like right angles that no car could ever traverse.
The only suggestions I'd make (based on recently getting my own road rebuilt on my layout and doing a lot of observations beforehand) is to have the normal road debris on the edges of the pavement, where cars rarely ever travel. A few small oil stains here and there, maybe a small pothole or two. Roads are just so random, once you stop and really look.
