Bug 1373244 intends landing dedicated profiles per channel. We should consider whether Sync should have UX to explicitly support this use-case, making Sync be the magic that helps share data between these profiles, somewhat similar to what we did for developer edition way back in bug 1079835 (but better) - for example, when creating or first using one of these new profiles, we could check if any other profiles are using Sync, and if so, show some UI to help connect this profile to that account. This is a meta-bug - I expect any work to be done in dependent bugs, but figured I'd get this on file to start the discussion.
Part of the discussion we've been having around bug 1373244 is how to create the new profiles for the other channels. One option is to do a full clone and I understand that would require some work on the sync side to duplicate the users credentials and authentication.