There is another one that is behind South Main RV and it is called, Lake View RV Resort
Looking at the map it appears to be a little further out than the main highway of Loop 610, which is a busy loop and South Main may be noisy from traffic.
Advanced RV is about 11 miles from Downtown Houston. (Bass Pro across the highway)
If you don't mind the 30 mile drive or so, there are several in and around Dickinson and League City that may be accommodation. There is a new one just across the line from Biyou Vista, in Hitchcook called Louis Bait Camp (Yeah, I know, but the bait camp was there first and the RV park was added jut behind it.) Sites are close together but some of them back up to the water with a walkway to fish from. I'd say it is about 40 miles or so to DTH.
So check out, Green Caye and The Palms in Dickinson, TX, and Space Center RV park in League City as possible other options. Green Caye is $370-380 a month with FHU.
Give a holler when you are in the area.