I have only done the trails up to Mt Sterling Ridge trail (Palmer Creek, Pretty Hollow and Little Cat/Long Bunk. Horse traffic heavy around the trailhead and maybe for .5 - 1 mile. Have seen horses once or twice around Laurel Gap Shelter. However I haven't done anything on the opposite side of the road (Southeast): Rough Fork, Big Fork, Caldwell, Hemphill, etc. Those might have more horse traffic.
Little Cat. Trail has some nice history (old homes, church and graveyard). If you are into that it is worth the hiking the trail. These trails also allow you to make some nice loops.