Lots of good info so far.

LED headlamp.
There is almost nothing as stupidly dangerous than trying to navigate a trail in the dark while trying to carry more firewood in, find your way back to camp after a call of nature or the like.
Making that fire after dark becomes even more challenging while trying to hold a flashlight (carry one also) where you can see what you’re doing.
I use mine all the time, working around the house, on the car, and when the power goes out occasionally.

Carry the hd contractors trash bags, they have many uses, but combined with a space blanket can create a sleeping area so warm you may forget where you are , at least temporarily.

Guidebooks! As many as you can on native species of flora and fauna for your area. Euell Gibbons books on foraging are worth every dime despite their age.
You don’t want your last words to be those of Socrates, “I drank what?”

Plan for the worst. Be it a blizzard in July (been there), multiple flat tires whole out for a drive or any of the little things that can turn a beautiful day into a tragedy.

And remember ultralight doesn’t always mean long lasting.