Another vote for Ft. Davis State Park. Note, my comments are based on a stay three years ago. Absolutely beautiful campground. Only place we could get Wifi was at the restaurant. Nice site with plenty of space. On our site the cable hookup was on the opposite side of the site and required a long run. Would stay there again if life takes us in that direction.
Will never forget the visit to Ft. Davis National Historic Site. It was haunting to walk around it while the outdoor speakers played recreations of the daily sound of a Calvary fort of the period.
Also not to miss the tour of the McDonald Observatory.