Yes on the FiberFix Emergency Spokes:
http://bit.ly/4YAKHSYes on the zip ties (don't weight much nor take up much space, very handy.
Yes on a small duct tape/Gorilla tape swatch.
The $20 bill could be put into use as a tire boot if a sidewall tears, but you could easily carry a piece of old Tyvex envelope as a lightweight but strong boot material to get you down the road.
Maybe a small "handy-wipe" towelette instead of the gloves suggested above.
Carry the sleeve that you cut off an old short-sleeve t-shirt. You could use it as a head warmer if things turn colder than expected, to bind or cover a cut, or as a clean up rag when you drop your chain.
I carry pain reliever, couple of alcohol pads and a couple of road rash or cut-worthy bandages. For ideas, search online for Brave Soldier packs.
I guess it depends on where/how far/how isolated you ride. A front brake cable wouldn't cost much weight nor room. Randonneurs are often well-equipped due to the sport's creed of self-reliance and self-support. Lots of examples online of rando kits.
Keep the rubber side down.