>>453481so a quick look-over of your gear, and seems legit. I wouldn't bother with the bear bag shit though. Nobody bearbags on the AT except the Smokies and Jersey, and there they have cables and boxes respectively. Jacket is your call-- it will probably get bellow 20 at least some days, but you'll probably be walking or in your sleeping bag. I worry about down jackets on the AT because of all the rain; I used a fleece jacket and I'm pretty sure it kept me alive during the freezing rain. I would probably stick with just the 2 Liters of water capacity. I never once needed more than that, though I suppose the big benefit of a high precip year is that water was never an issue (except below freeing.) Anyway you'll figure out your gear for yourself along the way.
I spent a little over 2K on my hike (not including gear) but I dirtbagged the whole time. I only slept in a motel twice (and then stuffed with people) and like maybe three hostels (a handful of church hostels though, they are a great deal in towns that frown on stealthing) If you have a taste for finer things there are some very nice places to stay, and eat, and spend money at along the way; you can easily spend 5-6K.
The only place I would say a maildrop is really necessary is Monson. A couple gas station resupplies along the way for a day or two, but the 100-mile wilderness is a long stretch to make on candy and Fritos (unless you're one of those no stove people in which case it's never far down any road to a Snickers Bar.)