I have been using KeePass for eight years. Used to just shuffle the file around with Google Drive, now I have it sync'd with Syncthing across a few devices. I use its notes feature to store associated data like S3 keys and it stores my SSH key and KeePassXC can automatically add it to an SSH agent.
I don't really have any complaints about it.
Related to OP's question: is it possible to have the 1B boot from something other than an SD card?
I ran it as a PiHole for awhile, until it chewed through two SD cards. I'd like to use it for the GPIO functionality but I don't want have it randomly crap out again.