Your setup is strikingly similar to what i used for my AT thru last spring. I started March 15th.
I am wondering about your sleep pad.
I used a Ridgerest closed cell pad but most other hikers used something more substantial like an inflatable or thicker closed cell foam pad.
Every year is going to have different weather of course, but for me last year, my coldest temperatures early on were found in the Smokey Mountains.
I had mid twenty degree temperatures overnight there for a few days.
Wearing all my clothes from skin out: Long sleeve nylon hiking shirt, Cuben Cloud Cape, Montebell Thermawrap parka (hooded), Patagonia down sweater, smartwool lightweight bottoms, smartwool mid weight socks, home made fleece mittens (worn on feet), and a baby Alpaca wool beanie (Thanks to Kat!).
All the above clothing worn while sleeping under my Mountain Laurel Designs Spirit Quilt 30 and I was just comfortable in the mid twenties.
Temperatures were confirmed by a fellow hiker's thermometer and the fact that every exposed water bottle froze solid by morning.
In my case my quilt fit over me, wearing all those clothes, without the corners lifting or compressing the fill of my clothes of the quilt. I could also roll over without dislodging the quilt.
I also noticed i was much warmer sleeping on the ground under my tarp than in the shelters.
Obviously this is all highly subjective to my experience. From what I saw I might be considered a "warmer" sleeper than most other hikers.
I can suggest that at some point you will want to send your warmer stuff ahead from perhaps Pearisburg, to maybe Hanover. The White mountains were the second place i saw freezing temperatures on my thru. Particularly Mount Washington where the day before my ascent the windchill was 0 degrees and some thru hikers were turned back by the cold.
You can find a lot of great information on gear lists other hikers have used succesfully at Trail Journals and Postholer.
I think my advice should be considered to be on the lighter side gear wise particularly for an AT hiker.
I wanted to add a word about the way i layered my clothes for cold. Notice i put my cuben cloud cape UNDER my insulation layers. This acted as a Vapor Barrier for my upper torso. In below freezing weather the effect is pronounced.
The vapor barrier did'nt have to be an expensive cuben fiber jacket. It could be a cheap plastic jacket.
The same thing could be done with your rain jacket so long as it does not cut your circulation by being bunched up or compress the fill of insulating layers of jacket or quilt .
I think this was what really clinched my setup and kept me comfortable for those cold nights in the Smokies.