Jobs I'd like to see in FFXIV.
I feel like if the next expansion gives us another 2 jobs it should be healer and rdps to even out the roles.
RDPS: Beast Master. Uses a whip and can "tame" various beasts in the world. If this would somehow be a "nightmare" to balance make the beasts purely cosmetic but the gameplay the same. Or sort of like summoner. You'd have like 3 stances. Agressive, Defensive, AOE.
Healer: Chemist. It's a theme that no other class touches on and I think would be best as a healer. It would be almost nothing like alchemy. It'd be abilities like any other class and you'd throw potions to heal and buff and debuff etc. A Jekle and Hyde ability might be neat.
Alternative RDPS: Puppet master. Would be similar to beast master Except wouldn't use any weapon they can attack with. Instead their weapon will be a control bar/strings. ALL of your abilities will be commanding your puppet/s. Having little to no abilities of your own. That is how it would be different from beast master but they're otherwise fairly similiar.
Alternative Healer: Time Mage. Turn back the clock with time magic reversing damage done. A buff you can put on yourself or allies that lasts a few seconds and all damage done during that time is reversed when it ends. Could come with some really neat animation. Mechanic wise it'd be similar to most healers but be very unique thematically.
Alternative RDPS: Gambler. Before you say "But that's basically Astro" and I'd say Gambler is to astro as Gunbreaker is to Machinist. Similar weapons some similiar concepts but different roles and would play radically different. Instead of cards by a side gimick like astro cards and dice will be your main thing and can alter the outcome of the battle. Abilities like increase crit chance, using cards to cast abilities, or dice to roll damage the enemy takes. (It's set is already in game!)
Alternative Healer: Merchant. Now this is kind of a ridiculous concept but it's been used in a few games and is mostly a support class. Obviously the class would be learned in Ul'duh. They'd use their own ability resource version of gil as their class niche. Has an ability similiar to ninja that makes enemies who die while effected by it drop more gil. Sacrifice your artificial gil to buy potions and other useful items from the aether. Big Pharma healing! (Your teammates will have to pay you back after a run ;)
Regarding Limited Jobs...
I think the issue with jobs like Pupettmaster and Beastmaster that they either have a collectables gimmick (consider how many of the minion pool are puppets) or could more easily be tied to one, thus not having a complete collection would be detrimental to clearing content in a normal DF environment, so as a result they would have to be Limited Jobs.
Granted Puppetmaster could theory work without using existing minions, but it would prolly be closer to MCH minus the guns.
Granted I'm of the seemingly rare opinion that the devs shouldn't abandon the limited job concept but focus on improving it and that if they were to be made into normal jobs, that they would inevitably start 20 levels below the cap as per dev and player convenience.
Of course this is off topic, so I give a more earnest answer for unlimited jobs.
I want to see a Rune Fencer/Mystic Knight/Magic Knight. a Swordsman that uses the En spells that exist in the game to enchant his weapons and execute attacks.
I want to see a Job that focuses on Symbols and runic powers, preferring drawing and drawing from the sigils associated with the Twelve to grant boons to the party and banes on the enemies (AKA a support class)
I want to see a Job that uses Hammers.