I just keep a (symmetrically) encrypted secrets file on my main work machine with a strong pass phrase stored in a gpg-agent. It's simple (emacs will happily transcrypt it simply by opening it) and amenable to straightforward backup/duplication wherever I need it, though obviously it does assume a command line and that I'm not exclusively on a phone or whatever (not that that's impossible, but...).
It also has the advantage of scaling in a straightforward way to other secrets that aren't "passwords", like credit card and other account numbers, SSNs for my kids, addresses for relatives who keep moving, etc...
Sounds like you have a good system. If you ever find yourself wanting some more convenience commands around a system that's just like what you describe, I wholeheartedly recommend Pass [1]. It's exactly like your homebuilt setup, but with a bunch of convenience commands and git integration built in.
It also has the advantage of scaling in a straightforward way to other secrets that aren't "passwords", like credit card and other account numbers, SSNs for my kids, addresses for relatives who keep moving, etc...