A quality firearm belongs in every emergency kit IMHO, although legal hurdles may exist. For example, a Hi-Point carbine isn't elegant, but it works.

Yes, I have ponchos. Little is more miserable than being cold and wet. It can also kill you.

And yes, there is a huge difference between a 3-day bug-out bag, a 3-week stockpile, and what effectively amounts to an abandonment of society as we know it kit. If you think that last one is a possible need, pre-positioning caches may be will be necessary. Practice gardening now, too, because it is not easy. But hunter/gatherers have also existed across the planet, so a more nomadic existence may figure into your schemes. Beasts of burden help, as might boats, solar-powered electric vehicles (maybe), and bicycles (definitely).