Great report, and nice first hang.
I love my HH Undercover and pad for chilly summer nights but it simply is not enough to get you down into deep winter temps. I love my JRB Nest for anything below 50, and was comfortable down to 15 with a Speer top quilt, and polypro set.
The UC simply adds a couple of months of comfort on either side of high summer IMHO.
As far as the Over cover: give DIY a try if you really want one (probably one of the easiest of the DIY projects to undertake), or ask around about the Bear Burrito Oven by Arrowhead Equipment and see if it would fit the HH Evader (plus it would keep your camo theme rolling).
Hope to see you in the Barrens or the ADK.