I don't know of any other trails with shelters. There are numerous trails with primitive camping facilities, especially in the state park system. There is also the 100-plus mile Lone Star Trail in the Huntsville area that offers a lengthy hike. Again, I don't know of any shelters.
In your area, you could try Lake Mineral Wells State Park, which has a primitive camping area. Dinosaur Valley near Glen Rose also has primitive sites.
If you haven't done so already, check out the Texas Parks and Wildlife site at
http://www.tpwd.state.tx.us/. Information about the Lone Star Trail is available at
http://www.lshtclub.com/. The Trail Between the Lakes in Sabine National Forest might be of interest to you. Check it out at
http://www.fs.fed.us/r8/texas/recreation/index.shtml.
Stay dry and warm.