RB,
I carry other stuff depending on my situation. If I am going to overnight I will have a sleeping bag, food, and some gear with me.
I do carry 550 cord all the time and replace all my boot laces with it. Just don't see a fishing kit and immodium saving me.
I am certainly not as skilled as many here and I am definitely limited by my outdoor exposure being on the eastern side of the U.S. I have NO desert or high mountain (Rockies) experience.
I have been out solo off trail on many occaisions and have done a good portion of the AT and some other established trails. I certainly have been in some tough scenarios, but I wouldn't necessarily call them life threatening. I have been in a survival situation outdoors, but a kit would have done me little good. Those experiences have kind of molded my preferences to go lighter and more basic for my toolset. I used to carry an extensive kit, but little by little, removed those things I decided I would never use. Eventually, all it had was a compass and waterproof matches in it.
Believe me, If I went out to the Rockies to head out in the big woods, I am going to listen to every piece of advice given by those that do it regularly in the area.
I am figuring this, and myself out as I go along just like the rest of the folks here. So, while I think I am pretty skilled, I don't consider myself an "Expert"