Looks like you know someone in the military with all those things you just "had laying around"

I got a bunch of stuff from work laying around as well. Thats a big rule in any emergency I recon. Learn to use what you have available. Theres nothing wrong with the pack in the picture if you can carry it comfortably (key word) It may draw a few looks, but it looks sturdy and the money you would waste on another pack could be spent on something you don't already have. If you cannot carry that pack comfortably you may want to consider replacing it then, as 400 miles is a lot of distance.

As far as reviewing you gear you must also consider that you are the only one who knows where you will use it, how you will use it, and all the other special cirmstances that would make everyone on this forum pack something different.(climate, topo etc)

I have no idea what a person would need to walk 400 miles in north Carolina, but as a Canadian I would trade 3/4 of what everyone else suggested and half of whats in your pack right now for warm clothes and a good broken in pair of boots. For me, my biggest considerations would be things like a wool toque, gloves, rain gear, a fleece or wool sweater, Good sturdy footwear, sunglasses, and like someone mentioned, lots and lots of water as well as as many ways possible to find and purify more along the way.

IMO, take it for what it is, Things like folding shovels, books, extra firearms, fishing gear etc are wasted weight. The chances of successfully hunting, trapping and fishing along the way will be a lot slimmer than you think. If the average person only knew how hard it is to "live off the land" they would happily give thanks each and every day they dont have to. You may be best off using that space for calorie dense foods like mainstay bars, or heaven forbid pemmican if you could stomach the taste. If it were me I would remove everything from its packaging unless totally necessary (like food obviously) Invest in a good solid water purification pump and add lots and lots of BLISTER BANDAGES TO YOUR FA kit. Trust me, I have carried a pack similar to yours for over 16 years and its the blisters that will bring you down first if the feet are not conditioned.

If you are not used to walking with weight for long distances taking the time to condition your body now may be a bigger investment than any amount of fancy gear you will stuff in that bag. I can't stress that one enough. Packing the bag is one thing, but carrying it is another. A 400 mile trek is a big endevor, even for someone like myself and I do this crap for a living. You may as well accept the fact that you will be carrying your little girl most of the way as well if on foot and alone. No kid I know is going to walk 400 miles. I can't get my daughter to walk to the dishwasher....Anything you could do to not have to walk would be worth consideration. You hate riding a bike? well imagine walking 400 miles through a huge emergency with bleeding feet, dehydrated and carrying a scared little girl on your shoulders with 300 miles to go. Right about then I bet the bike would sound pretty good. Not trying to sound snarky, just saying.

In the end, know that every oz of weight you carry must be worth it or it is a waste. If you can't realistically find a god reason to carry it then learn to live without it or learn to improvise it on the fly (like the pointed stick vs shovel that lessnyder pointed out) Stick to the basics (like proper clothing, water, shelter) and get your body ready as best you can to be able to make that 400 mile walk if and when you ever have to.