I would say that this one looks best so far from your attemps.Still I would prefer to show us the same texture in dark and brighter version next to each other.
I am using for this exposure in PS rather then brightness and contrast settings as it doesnt affect much the texture itself.
I like the lighter one. It almost looks as if it had specular highlight (like real asphalt/tarmac). Maybe a bit too much, though, but overall, I think it's really getting there.
PLEEEEEEASE go for the white and blue curb look. Westhill already reminds me of Silverstone, feels like driving on an abandoned WWII airfield in the riginal, this would just SO make it Silverstone (except the layout :P ).