Great idea! I’ve pinched a couple of yours for my general setting:
Hide windows | Create an empty note | Zoom (useful in lessons) | Left 2/3 | Right 1/3
XCode:
Run | Comment out block | Re-indent block | Backup current project | Speak selection (useful to know how Siri will say something).
I added one or two extras to individual apps, but I’m keen for other ideas!
Finder: reveal Yoink.
Chrome: reload the current tab as cmd-R doesn’t always do it.
iTunes: add artwork and lyrics to my songs (after bouncing from Logic)
Notes: Speak, to speak the text
Preview: Close current pdf and open it in PDF Expert
Simulator: Backup my current project (I’m still a bit uncertain of git)