No immediate plans for oauth although that's a possible development. It would be just more complex to implement correctly than the simple token strategy implemented currently.

I don't see the value it would bring to the end-user though.

For OpenID, I don't see any simple way to implement it as it requires an HTTP browser to be able to log into the producer site. The Nuxeo Drive desktop client is a… desktop client, running independently of the client browser. We could try use the WebKit browser widget that comes with the QT library but that sound very complicated to implement and the user interface would be awkward for the users as well.