From what I gathered in Yoshi-P's letters, I got the impression that they were not so much looking at adding advanced jobs but rather looking at re-creating the existing jobs, so that Conjurer would become White Mage instead, Lancer replaced by Dragoon etc, and a re-allocation of class-specific abilities to go along with it and re-balance the combat system. Of course, I may have read this wrong, but it was the clear impression I got (and if true, something I would be strongly against).
I would prefer it if we got Musketeer, Arcanist and Shepperd as regular jobs first. Maybe also add a new magic class for Ul'dah's Nald-sect rather than just having the Thal-sect available as Thaumaturges.