Currently you can convert Password items to Login. That's handy, but it sure would be great if you there were more supported conversions. In particular, I imported a bunch of items from my old password manager and as a result, I ended up with a ton of Login items with an empty username that should really be represented as Password type (or sometimes Secure Note). Obviously bulk convert would be great, but in lieu of that larger, more significant feature, a trivial stopgap would be to just have the "convert to X" button (same location as existing) for Login items that don't have usernames.
This pattern could be employed to support lots of conversions I have wanted for. If multiple "destination" types are possible, the interface could be adapted with minimal additional UI/UX work (e.g. dropdown instead of button):
Src: Login with empty username
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