This is one of those very rare cases with potentially huge negative effect to make it into a mandatory feature.
> Dumb file storage
Which still suffers from inefficient incremental updates. Curious whether those other managers deal with that (do they split your vault into parts)?
> What kind of documents would I put in a password file?
Whatever documents you want to securely share with others, various scanned docs, so it's not just a few megs, (e.g., Bitwarden offers up to 1G encrypted file attachments) (though don't use this either, mine is just a few megs)
The only thing you would need to make mandatory is a direct login to any storage service.
> Which still suffers from inefficient incremental updates. Curious whether those other managers deal with that (do they split your vault into parts)?
If it's a megabyte, who cares? You could have a way to split things or upload an update log, but it's not worth it.
If you need big attachments, then keep them outside the core vault file.
> Whatever documents you want to securely share with others
Sharing is where a dedicated service is useful.
But if a feature like that needs a paid service, it should be an optional upgrade.
Right, my main concern here is programs that talk directly to the service's API, because that's the easiest to implement in a correct way. Dumb file storage, but without the worry of stale versions appearing.
Though most people don't need their vault to be robust against simultaneous offline edits from multiple devices.
> (also I think it's more than a sub-Mb, you have icons there, but also images of docs and what not)
I have usernames/urls/passwords, some notes, some icons, and some ssh and bitlocker key files. In total it's 159KB, including a bunch of version history and the recycle bin.
What kind of documents would I put in a password file?
Though some extra megabytes don't really affect my argument much.