I have been wondering what new classes and or jobs we could see in a future expansion. Some ideas I have are below:
DANCER (DNC) it would be part of pugilist class and be a secondary job along with monk. It fits here due to the flexibility and dance like moves the pugilist already has. The guild would be located somewhere in Ul'Dah; as that is where we see a lot of dancers and where the pugilist guild is already at home. You would need Pugilist at 30 and Conjurer at 15.
DARK KNIGHT (DRK) it would be of the gladiator class and be a direct opposite of Paladin (even going as far as requiring the thaumturge class to unlock as opposed to the conjurer class for the paladin). It would also focus on shield and sword but would be purely a TANK as opposed to a TANK / SUPPORT.
MUSKETEER (MSK) it would another ranged attacker like the archer, but it would use guns. Guns are already present in the game, just look at most of the NPCs in Limsa Limonsa. Also there are signs depicting two pistols crossing each other in similar fashion of swords and axes for Gladiator and Marauder. This would be new class instead of job and would open up a new job of CORSAIR (COR) which would be a pirate based class. The MSK would be a DPS as well as the COR. To get the COR you would need to have 30 in MSK and 15 in PUG.
VANGUARD (VGD) is a disciple of war class that uses great swords and heavy armor. It is a tank through and through. It would be found in Limsa Limonsa. Its sole purpose is to give us yet another weapon type in the game. We have axes and swords and pole arms, and bows and staves and wands/scepters and books but we do not have great swords. So this class would give us that. It would then open up a new JOB which would be the Red Mage. RED MAGE (RDM) is a disciple of magic and war class, a true hybrid. It is an enfeebler class and would incorporate skills from both the THM and the CJN, but as is the case with all RDM they would use them at a much weaker attack with those skills. This would also be a new class. It would primarily be a fighting class, incorporating great swords and imbuing them with magic (from the CNJ and THM skill). In that regard that already nerfs the already OP RDM but still makes it a viable option. It would wear armor much like the MRD and GLD. It would be a JOB instead of class and would require a level 15 in both CJR and THM and a 30 in a VGD.
CLERIC (CRC) is a disciple of war class that uses hammers and heavy armor. They are a tank. They would be found in Gridania. They would; just as was the case with the VGD, fill in a void of another weapon type. They would use hammers. They would open up a new JOB called the PRIEST (PST) which would be more of a support tank. They would require you to have 30 in CRC and 15 in CJR.
SWORDSMAN (SWD) is a disciple of ear class that dual wields swords and daggers. They are a DPS and would be found in Ul'DAH. They would open up a new JOB called the FIGHTER (FIG) which would be a DPS still. It would require 30 in SWD and 15 in MRD.
Let me know what you think of them. There are a few more I may add at a later date. Most notable to the disciple of magic.