Used the same approach, but with a google drive document instead of dropbox. But you can't skip updating all (or at least, most of the perimetral ones ) passwords when a employee leaves (unless you trust him even after he leaves). If he made a local copy of the Keypassx file (or even pasted every password in a document, to cover most of the other alternatives) removing access to dropbox or changing master password will not stop him to keep accessing the old passwords. And the same goes with certificates.