You sound well prepared and your logic seems well thought out if I do say so myself. I like the idea of bugging in if possible. It is surely better to defend a hardened base than to strike out on your own. I also agree that bugging out is best done as light as possible if you are able and willing to live off the land. Being a hunter and outdoorsman helps to no end, I think. Being able to set up camp in short order, make shelters, gather or hunt/trap food and gather/purify water is really what HAS to happen. If you have these skills, you can even get others who don;t know how to help out by delegating and showing them how to get along. You can really turn people who are liabilities into assets like this. They may come empty handed asking for help so they literally don't die. The good skills you have can keep many people alive in a DD situation.
I also agree on your ideas of what is realistic as far as crisis go. Many of us prepare for flat out ridiculous scenarios, and even more of us prepare for things that CAN happen, but are really, really, REALLY unlikely. While I think it's best to be prepared for as many things as possible, I think focusing on what's a plausible threat can help you be better prepared by focusing your efforts on likely situations and realistic approaches to surviving. I know quite a few people who have stocked up on TONS of food and water, but live in high-risk areas that they would have to abandon in the scenarios you have penned. These same people have VERY limited outdoors/survival skills and would likely be just the people I was referring to earlier. Willing, but unable. Just the kind of people that you can turn into "Survival tools" by teaching them what you know and what you/they will need to do to make it.
Ya, I think you hit the nail on the head.