It works. Even the yellow.
Your gear list looks a lot like mine!
Your pad might slip around in your hammock unless the hammock has a layer underneath. Nevertheless, having a pad works well in shelters or if you just want to sleep on the ground, not use your hammock some nights.
I, too like having a three liter capacity for water. Although I never carry more than 2, If I load up with three in the evening I won't have to get more in the morning.
I have used dry bags for food, but you can find lightweight bags even plastic bags from grocery stores. You can use an empty stuff sack from other gear to to hang food. Many use compactor trash bags, but I like MYO different color solnylon or cuben fiber, or othert scraps for stuff sacks.
For your camera, look for a model (Canon Powershot models) or Kodaks that use regular AA or AAA batteries. The you won't have to worry about chargers. No need to carry extra batteries, just buy fresh ones as needed. Lithium work best in the cold.
One good aspect of the AT is the many opportunities you will have to swap out gear, send stuff home, or get new. 30 miles from Springer the trail goes right through the famous Walasi Outdoor center!
I prefer this guide book, not the big section AT guides or Data books:
I would start your hike with a 20 degree bag. In March you will find shelters warmer than hanging, I think. Get to your night spots early, so you can get a roaring fire going in the cold at designated fire pits near the shelters.
BPL has directios for MOG bags, too.