Two things for you to google - Speer Pad Extender and double layer hammock.

Many models of hammock have the option for a double layer version - that's to slip a pad in between the layers. Works pretty well.

Speer doesn't make the pad extender (or anything else) any more, but you can replicate it cheaply enough. A couple blue ccf pads and some duck tape will do. Chop one up to make wings down the sides. The only trouble is packing it. I was working up a light polyester sleeve for my main pad and blue ccf wings to attach to it via either straps or smaller sleeves.