Personally I would love a Corsair/Pirate themed job that uses a cutlass/pistol combo. Sort of an inverse Red Mage where you go melee to build up a gauge and then jump back to to a ranged burst. Also I don’t think we have enough Pirate aesthetics in the game at higher levels. I think it would also slot nicely into using Scouting gear alongside Ninja.
I was also wondering this myself. I won’t complain about getting new jobs every expansion, but that is more work on them (and more time spent leveling yet another two jobs to max). I think there might be some holes they can fill here or there, but eventually, I’d guess they’d say enough is enough!