Gun mage with elemental bullet enchanting would be nice but it conflicts with monk even though monk shouldn't have elemental fists to begin with in my opinion.

Thief is obviously something that should be added but you have to remember ffxiv currently hates you for being a melee on all content in some way or form of aoe you can't dodge if you ws once at a bad moment.

Red mage would be nice as well for the current environment to provide at least one more healer other than the white mage, of course, red mage would use a "sword"... shrug

Summoner is going to be added first of all the pet classes, pretty much no doubt that's why they chose primals for pre-2.0 content