Oh man, I don't think that essay would fit in a HN comment. The biggest one for me though was keyboard operation - I have fine motor control problems so try to use the trackpad as little as possible. 1Password used to have two different global keyboard shortcuts, one for the regular autofill interface and another that would pop up a mini version of 1Password that was fully keyboard navigable and could do almost everything the full 1Password app could do. I could hit Cmd+Opt+\ from anywhere and then entirely through keyboard interactions do almost anything I needed to do. This has been replaced by one global keyboard shortcut that only works if your focussed app is a browser with a login screen on it, and even then it often needs hitting multiple times in order for the interface to appear, and sometimes never appears at all until you finally give up and launch the 1Password app, and then magically you get the 1Password app with the 1Password mini interface over the top of it. It's one of the most frustrating experiences imaginable when it used to be such a useful thing.