Mark,
You mentioned wanting to get away from the crowds, so maybe you might want to check this Texas campsite out sometime. We've never been there, but the description sure reads nice. (BTW, for extended dry camping and boondocking in our Class C, we use a super quiet Honda EX650 generator for keeping the batteries topped up.)
This just might be an ideal remote spot in Texas for a popup camper (high enough to be out of the heat, too):
http://www.nps.gov/gumo/planyourvisit/dogcanyon.htmHere's a little more info on the area:
http://prism.texarkanacollege.edu/bbvirtual/dogcanyon/dogcanyon.html