I misread the OP. Roads do look pretty strange when you zoom all the way out to globe view, but I don't know of a solution for that. Maybe it's worse for BUG's roads because there's more contrast between colors.
The problem I was talking about is the fact that if you zoom out just a little bit, all of the highlights in the road textures fade out and what you see is a much darker, less detailed line. This is a side-effect of typical texture reduction methods. Load that mod_roads.dds file in PS or Gimp, or whatever, and resize it to 50%. Pretty terrible, but I guess Firaxis decided it wasn't a problem because the darkening actually makes roads more legible against the brightly-colored vanilla terrain.
There's no reason the mipmaps for BUG's modern roads can't be tuned to keep the painted borders visible at medium range, but now that I think about it, the best thing may be to just make modern roads a solid black line from the get-go. It would look about the same as it does now at medium zoom, and you wouldn't get that yellow weirdness in the globe view.