I like state parks and this is a good example why. The sites are well spaced, well maintained and relatively inexpensive. About $20. You can reserve online and the web site has photos of the site so you know it works for you.
Site have electric and water and the dump station is at the entrance of the campground. Easy to hit on your way out.
There are plenty of hiking trails and they have alligators.
If you're looking for a good campground close to Houston, this is your place.