Big Agnes makes inflatable sleeping pads that are just outstanding! Not a cot, but MUCH smaller and lighter and very comfortable. These are what I use for backpacking and airplane camping
I'll second anything with Big Agnes. I have the Big Agnes Lost Ranger bag, which is kinda a semi mummy bag, which was much more comfortable than the regular confining mummy bag. What I like about the Big Agnes bag is instead of down on the underside, which is normally compressed and not efficient, it has a sleeve that you insert your pad or mattress. I like it because you then always have your pad under you, instead of waking up and find your've slid off your pad or you're trying to keep on it throughout the night. Keeps the weight down because you can get by with a smaller pad, and Big Agnus can add more down to the top for a higher rating.
It seems that as I approach "the new 40s" my upper body is a little more bonier and my lower a little more softer, so the cot such as the Thermarest or Sleeprite eliminates the soreness I get in my shoulders and arms from sleeping on the unforgiving ground with just a pad.
A Big Agnes bag with 2" inch inflatable mattress, a lightweight cot like those mentioned, Tennesse Tea, and I'm good to go. One of many approaches to the good nights sleep issue.