I've had to do this twice, when a rear spoke broke and threw the now wobbly wheel into the brakes.

Well, actually, the first time it happened, I didn't have the spoke wrench and had to ride the 5 or so miles home with the rear brake rubbing in a very annoying manner. That's why the second time it happened, I had the spoke wrench and was able to straighten the wheel enough to finish the ride.

Since that spoke broke 30 miles into a very hilly century, I was able to ride the last 70 on that gerrymandered wheel. The 40mph descents were a little nerve-wracking, but having to quit would have been far worse.

I think everyone should be able to fix a flat, and carry the stuff to do it. I've considered leaving people who don't do that. Personally, I can do most things on the OP's list, but wouldn't want to build/true a wheel from scratch. Funny thing is, while I carry a small collection of tools on every ride, but no chain tool. Maybe I just haven't found a small enough chain-tool for the Campy ultra-narrow chain.

A broken chain on a ride is my Waterloo.