There is something to consider in regards to jobs we'd like to see in the future, and that's how closely their main mechanic would translate into an MMO setting, plus is that mechanic already in the game in some form. For instance Mystic/Magic Knight/Spell Blade enchants their sword with magic to do damage, but that concept is similar to what Red Mages do, albeit slightly differently. Many common Ranger skills have been given to Bard, and many Time Mage skills to Astrologian. That isn't to say those jobs cant be implimented, but they would need more unique identities than what they were/are.