True, at some point FFXIV will start having exclusive jobs. However, we will have every nostalgic job in-game before that happens. Exclusive jobs could still have nostalgic parts. For instance, they could add a completely new job concept that features the gunblade as a weapon.

I am curious about the battle system changes though. Will they be as heavy as the transition from 1.0 to 2.0 was? Maybe not, but hopefully the changes will not be too minor. For the current info we have, simply toying with cross-skills doesn't really imply much of a change.