We have stayed at several COE camps in Texas and other parts of the West. Primarily, we look for COE camps with at least water and power. We like the larger campsites, so no one is smack against you. Most COE camps have hosts, but no paid personnel between 4 PM or 5 PM and 8 AM. Emergency numbers are displayed on the office window, if you need someone. We have never had a problem with other campers in COE camps.
We stayed at the MIdway COE in Waco, which was very nice. It's on Lake Waco. I understand the Airport COE is very nice, too.
The COE has a website that gives info on each of their camps, or you can check out Campground Reviews (formerly RV Park Reviews), http://www.campgroundreviews.com/
They give a lot of information and reviews on over 17,000 campgrounds, which we have found to be pretty accurate.
Have a great trip!