We've just returned from Big Bend and did a little reconnoitering on the parks available. If I had my druthers I would stay at
Rio Grand Village RV Park - Full Hookups. Unfortunately I didn't make reservations in time to get there, but we went by there, and there are birds galore and you're yards from the river which means you have a very lush ecosystem to enjoy. You can't see the river because of all the over-grown bamboo, but you can walk to it through hiking paths all over. The sites were spaced nicely apart and it looked clean, although we don't really use the bathrooms and such. The park has a "store" which has some basics.
We stayed at the
Big Bend Resorts and Adventures RV Park because of the location (central between state & national parks). There's also another park in Terlinqua-Study Butte
BJ's RV Park, but either park in Terlingua looks about the same.
The RV Parks inside the National Park are pretty standard (except for the Rio Grand full hookups), and have limited hook-ups. I wouldn't try and do anything real big on that road up to
Chisos Basin which is beautiful, but windy road to get to, but do go visit after you unhook. The other parks are basically primitive. We didn't check out Persimmon Gap - I don't think there is campground there.
It's a dry ecosystem there, so most parks are gravel with lots of dust - that's just the lay of the land. Except for the Rio Grand which has the river for irrigation and Chisos Basin with is a mountainous system. That part of the fun of Big Bend!