I think if you can move up to the next class of vehicle to tow with, it would be worth it. Parents Yukon netted 14mpg towing to Canada. My Suburban is 8mpg. But I can't tow down to KY, TN with the Yukon cuz the hills absolutely kill it, I was about 9mpg and still 8mpg with the Suburban. Shave some pounds, reduce a bit of wind drag, maybe tire drag, you could probably get the Yukon to go through KY without running it to its limit. And that would be totally worth it for me. Their Yukon nets around 17+mpg hwy unloaded and my suburban is 10mpg.
I remember towing our quads with a single axle. It was a bit of a PITA to balance it just right. Especially when I towed with my Cherokee, it was picky about tongue weight...