Great post and great idea! I'd like to add some items or alternatives for a starter kit. A little back story. I'm an old Army Scout and spent a lot of years in the woods. We learned to pack light, pack efficiently and pack for worst case scenarios.
Here are some ideas to consider:
Backpacks:
A. I prefer a pack that has a frame. (internal or external) comfort is key. A pack rubbing in the wrong places can really wear one down. Frames have a way of dispersing the load evenly. Loads settle in frameless packs adding stress to your lower back and shoulders.
B. Something with a detachable daypack. If you have to set up camp somewhere, it's nice to have a daypack the can be detached and used for short treks, exploring, foraging or whatever.
Necessities: IMHO
1. Sandwich bags and some freezer (roll your extra socks, shirts, undergarments etc.) and store in these. Try to keep all packed items dry at all costs.
2. Garage bag (large enough to cover your pack if needed)
3. Waterproof matches, lighter etc. I also buy the small starter logs (size of sharpie markers). The less energy you need to exert to start a fire the better. You burn a lot of calories in the field.
4. K-bar or Machete. Also a Gerber multi-tool, Leatherman and a 3-5" knife with locking blade. I prefer Gerber. You can pick these up at your local Army/Navy store for $15-25 and they are bulletproof or as we said Joeproof. Someone had mentioned a small wire saw. I have firsthand experience with these and you will expend A LOT of energy using these. Blisters, muscle failure, the whole nine yards trying to cut something.
5. A good Atlas, or some quad maps of the ares you plan to be in and a good compass. Electronics fail, batteries die. A map and compass can be a life saver. We used to use our GPS's periodically to get a fixed position when needed and use the maps for the majority of our navigation. You'll learn the terrain better and recognize terrain features easier this way.
6. Field stripped MRE's (remove all unnecessary items and duck tape close) Ramen and other easily prepared meals
7. Small field burner that can be used with a small propane tank ($10) a field mess kit.(fork/spoon/knife combo.) canteen cup/ mess plate.
8. Poncho and poncho liner. 2 ponchos preferably. One can be used for shelter and the other can be used to wrap up in and when used in conjunction with liner, can be very warm.
9. 550 parachord and duct tape can fix just about anything! A couple locking D-rings are useful for a field expedient pulley. You can also hang items with them (keep the rodents out of your pack and your food) a raccoon can reek havoc on your food supplies.
10. As much water as you can comfortably carry. 2 qt. canteens (soft shell) can be attached to the outside of pack for extra. Some water purification tabs (emergency) and a bottle that has a filter if needed.
11. First aid items:
A. Aspirin, tylenol, ibuprofen (just ideas) this stuff comes in handy when your sore.
B.. Gauze, bandages and a pliable quick splint.
C. Anti-bacterial lotion of sorts. Untreated cuts can become infected quickly in a field environment.
D. Foot powder, tooth brush, toothpaste and toiletries (soap). A small wash rag and towel. You can't imagine how brushing your teeth, washing up, dry feet and a fresh pair of socks can make you feel. It's a huge psychological boost!!
E. Bug spray!!
12. Portable radio, 2-way with weather. Extra batteries. Mag light or Led light. Chemlights are a good option too. (Light sticks) help conserve batteries.
I like the military surplus stuff myself. The box store stuff is cheap but it is Cheaply made and fails when put to the test. Clips break, straps come unstitched. The ponchos tear and become brittle in colder temps.
Take your time a buy quality items that will last and not fail when you need them the most. It is stressful enough in these situations and not having to worry about your equipment failing is huge. Good luck and I hope I've added some insight.