I would add a couple of things, just having come back from camp:
1. Baby wipes (or equivalent). They have replaced TP in my daypack. Nothing like camper butt to make things unpleasant.
2. Consider a GPS app for your phone. I am using GAIA on my iPhone, $19.99. can download topo and/or satellite overlays. Phone can be on airplane mode (meaning the battery lasts a long time). Downside is charging, since the battery is not removable, so you have to bring spare storage type chargers. Your choice to balance cost/benefit.
I use the ankle express (decidedly infantry, not cavalry), so I have to tote my gear on my back when hunting. My hunting partner gives me s**t without mercy for how much gear I carry in my pack, but I figure sleeping the night in the woods is better than dying out there. So the hunting pack can be weighty, but I would rather have it and not need it....
And referring back to cotton - these days the underwear companies make your whitey-tighties/briefs/boxerbriefs in synthetics that are comfortable and that don't hold the body odor like cotton. The only cotton in my gear is my bandana.