Looks to me like it is a good start and it covers the basics.

I think the idea here is that if you prepared enough to have a three-day kit that your smart enough to be wearing appropriate clothing and both sturdy boots and long sleeves would be covered. A spare set of socks, underwear and tee shirt would fit.

I think a multi-tool like a Leatherman Wave would be a nice addition but then again they may be assuming you have one on your belt. Similarly ID, contact information and such would be in your wallet.

A 50'hank of light line might be good. It doesn't say what is in the first-aid kit but most are little more than a couple of band-aids, three feet of tape and a couple 4by4 gauze.

At a minimum I would add a selection of OTC meds. A dozen each of Pepto tablet, Imodium, aspirin, Tylenol, Benadryl and Chlortrimeton would be a good start. A roll of athletic tape, a couple of triangular bandages and a stack of 4by4s would give it a bit more depth.

A small bottle of bug juice, a boonie hat that has been soaked in silicone and a head net would keep the rain and sun off your head and keep the bugs out of your face.

A light poly fleece blanket would come in handy.

Two or three large heavy-duty garbage bags would give you some options.

A spare bulb for the flashlight and spare batteries for the radio and flashlight would be good.

If your going into a shelter earplug, eye cover and a pack of playing cards would help some.

A simple hygiene kit: toothbrush, toothpaste, travel size deodorant, razor and shaving oil, washcloth and small towel, and a travel size soap would help to keep it clean. Brushing my teeth and shaving always makes me feel more civilized and I can do it with little or no water. Baby wipes are okay if it is the best you can manage but if you can squeeze out a pint of water a [censored]'s bath getting the rough spots with a wet washcloth is better.