Can't help directly but consider the parks with full or limited cabins.
TPWD: Lodging
you may need to scroll around the link to see full cabins
In January we met up with the campermon family at Cooper Lake SP (South)
we were in a full cabin, she was in a limited cabin. See the post, for pictures.
Both were good places (full cabins cost more and offer more) but after seeing the limited cabins they could work for us too if needed. (We have a hybrid trailer normally)
Cooper Lake SP in a cabin January 2009