I agree, roads are a tremendous challenge, but I think you're on the right track with adding some shading to them to connote ruts. The dark lines on the trees stand out a bit; maybe try using a slightly wider and softer brush at low opacity to fill them out.
The cattle are great (they look like burly bison to me) and I like the go at hide-stitched roofs you've made.
cheers,
Meshon