Great subject Craig!
I guess I think somewhat differently, we all do here and there. I prefer to carry less but take only tested, reliable items that I know I can count on.
I shall share what works for me, not to say your list won't, you take what you are comfortable with.
Knife, usually two, a solid fixed blade with full tang and a locking blade SAK. No multitool, too heavy for wilderness carry.
Water purification, a MSR mini-waterworks and back up with some Potable Aqua tablets.
Water carry, a Camelbak 100oz and a Nalgene 1L bottle. Never put all my water in one basket!
Condom, NO, they are for entertainment, not survival:)
Space Blanket, nope. The only use I ever found for one was to defeat heat seeking sensors on an AC-130. I had the military one which is green on one side. It was effective in that roll. Although the crew later pointed out if they had lit me up with a few miniguns I would have likely bolted!
Dental Floss, yeah, handy stuff.
Surveyers tape, no. I can always strip up a piece of bright clothing.
Whistle, mandatory. I use an ACR I like the sound and size.
Firestarting, a FireSteel a BIC and some tender quick tabs. I also carry SA matches in an old BSA matchsafe. Goes back to my youth. I do not treat the matches, makes them go bad sooner in my experience.
Magnifiying lens, a credit card size fresnel. Handy for reading in bad light with my old eyes. Can start a fire with patience, sunlight. A last ditch method to me.
Light source, a Black Diamond Xenix IQ. Good battery life, light can be used hands free since it is a headlight. adjustable lighting.
Spare batteries, yes sir.
Drinking tube, well the Camelbak has one built in. I also carry 3ft of silicone tubing, flexible and does not dry out as easily as some plastics.
Water bladder, sometimes take a MSR Dromedary.
Poncho, a nylon decent quality one with the extended pack back, ties for guylines and staking.
2 or 3 30 gallon trash bags. Black because they are heat attracting. Also a TMRU tube shelter. light bright and will cover well.
Wool hat, always.
Cotton bandana, almost never.
50ft 550 cord and 50ft of lighter mil-spec nylon cord. Does loads of things on one light package.
Signal mirror, yes indeed. I use a military plastic one with built in removeable protector. Peels off and sticks back on when not in use.
FAK, Adventure Medical .7 model with a few extra items.
Map and Silva Ranger compass. I prefer 15 minute maps, 4 times the area for one map. Getting harder to find these days!
Snack food, gotta have it.
Snake bite kit, yep it's a military web belt also used to hold up pants.
I have a few other items but this list is long enough already!
Cheers!
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No, I am not Bear Grylls, but I stayed at a Holiday Inn Express last night and Bear was there too!