You might like some of the other state parks in East Texas; we certainly do.
Caddo Lake - interesting bayou-type lake, near to historic town of Jefferson
Village Creek - in the ecologically interesting Piney Woods. Canoeing can be done on the creek
Martin Dies Jr - east Texas hardwood forest ecosystem, on a nice lake
Sea Rim - haven't been since it was wrecked by Hurricane Ike, but I understand it's been rebuilt. When we went it was a nice beach park.
If you head more westerly into the Hill Country, there are a lot of great parks there too. I'd basically just be pickling off a long list of the state parks - so instead maybe take a look at
http://tpwd.texas.gov/state-parks/nearby/all-parks