I apologize for the double post, however, this is a topic I've been interested in for a while now and haven't had a whole lot of time to really look at your list. Now I do and would like to get some of your thoughts as well. I'll warn you that I'm a minimalist in most aspects of life, not just backpacking.
Have you seen Don Rearic's website? If not I suggest you google him. There's lots of interesting reading on his website, particularly the parts about his experience as a homeless man.
My personal take on your list is that a smaller fixed blade is easier to explain away and won't scare as many people. Something like a Benchmade Nimravus Cub or Esee RC-3 is what I'd go with.
I'd probably drop the headlamp and retain the regular flashlight on such a trip because trekking poles would pretty much be out of the question anyway and I'd want to save on weight and space. If I need hands free I'll hold it with my mouth or turn it on high and stand it up on end... not as effective as the headlamp but still adequate in my opinion. My experience with the Fenix L2D has been good. I like it because it takes AA batteries, has decent battery life on the lower settings, and has survived to function after quite a few impacts. Have you been trained in how to use your flashlight for self defense? If not, and you have the intention of using it should the situation arise then I'd look into some lessons. It isn't a difficult thing to use but some practice could go a long ways.
I noticed that all of your fire starters are dependent upon being dry. I think I'd carry a couple of mini bics and a small fire steel. If not I'd still carry the fire steel since it makes for something to do even if you aren't well versed with it - you can always practice when you're bored!
Are you carrying all of these clothes or are these what you're wearing too? If it's carry I'd think you'd be able to cut down on some things here. If it's the clothes you're wearing too then I'd still think long and hard about all of them. Particularly the second pair of pants and second shirt. It seems people have traveled with a lot less, that is, the clothes on their back and some extra socks.
The pack I've been eying for such a trip is the Golite Pinnacle. This may not work for your weights though. Do you have any idea how much all this gear is going to weigh? How much food you're going to be carrying? The amount of water you have the capacity to carry is significant in and of itself.
I like my flat tarps for the simplicity, weight, and size (both coverage and packing size) however for such a long trip I'd probably choose a tarp tent of some sort. Possibly the original and a silnylon or cuben fiber poncho tarp as a back up shelter and backup rain gear. I'd want to be able to implement it into my primary shelter for more room on days where I'm lounging in/around the tent.
I'm sure you'll have to check this load into baggage to travel so some of the smaller essential gear and a backup shelter/rain gear in a light weight "peak bag" (a dry bag with straps possibly) might be in order. I figure I'd use it for my sleeping and clothing normally but reallocating your gear for flight would be a good idea since you never know when they're going to lose something.
Those are some things to think about anyway, if you haven't already, and I look forward to hearing your thoughts on these subjects.