For 3, a monetary union isn't necessary; look at the US & Mexico & Canada, thanks to NAFTA. Certainly helps, though. I don't really see any areas which might do this sort of thing. Open borders and no trade barriers is a very Western 1st World sort of thing to do, and the obvious candidates like Japan don't really have an incentive to do so. (Japan has no land borders, so having passport checks doesn't really increase the cost of flying or boating to it.)
For 4: I think custom-fitting is already possible, and has been since the early laser scanners came out in the... '80s? But like the sous-vide, I'm not confident in their uptake. (It's kind of like jetpacks and flying cars and pneumatic postal systems. We have them; we just don't use them.)
ETA: The website didn't just format the numbers into pretty paragraphing, it "corrected" the numbers.
This is part of standard markdown; you can number each item '1.' if you want! If you want a number item you can escape it with a backslash, or you can do like I did and insert a paragraph after the bullet (newline, and then indent the paragraph by 4-5 spaces).
Damn, on 3 I didn't say what I meant. The genuinely big deal is freedom to relocate and work.
Do you have a source for computerized custom-fitting of shoes? The big deal isn't just the fitting, though, it's reasonably-priced manufacture.
Afaik, jet-packs can be made, but carrying enough fuel for significant travel isn't feasible.
As for flying cars, it finally occurred to people that there were weather and pilot safety issue.
I don't see those sorts of considerations applying to sous vide or computerized custom shoes.
The futuristic prediction which seems to be not happening because people just don't want it is video which shows your face while you're talking on the phone.
I would like to propose this as a thread for people to write in their predictions for the next year and the next decade, when practical with probabilities attached. I'll probably make some in the comments.