I started to fill a bit of chill through the bottom of the hammock and I decided to put my 3/4 length REI brand self inflating pad (1.5 inch thick) under the supershelter pad, inside the undercover.
This probably the area to improve. I bet it did not help much used like that. You need to have good contact with the pad to get the insulation value from it. My buddies have slept into the 20's with this pad and a good sleeping bag. I would try laying on it in the hammock just to see if it improves quite a bit. I know that using the pad in hammock can be a pain but I bet you could have stayed warm. JMHO, and my wife says it's not worth much