New Jobs off current Classes!

[Gamemako]

Anyway, here's something to keep in mind. There is no support role in ARR; it's just a focus of a DPS role. It is unlikely that there will be two jobs which are both DPS from the same class. Ask any BRD how much that "support" changes their gameplay and stat distribution. As such, every job will need a complete role change across jobs.

Gladiator (tank)
Current job: Paladin (tank)
Available mechanics: GLA has no unique mechanics
Present ability set: Hate generation, damage reduction, the odd MP recovery
Potential jobs (DPS): Dark Knight, Mystic Knight, Templar
Potential jobs (healer): Templar (?)
Notes: GLA has no healer-appropriate abilities and few attack abilities. It needs a job focused on inverting everything that a GLA does, perhaps using the enmity generation as a damage mechanic. This would be most appropriate to a Dark Knight job. Mystic Knight could also possibly be used, making use of the MP regen from Riot Blade, but you would need a use for all those defensive and enmity-boosting abilities. Templar would be another possibility, having a lore reason to exist (especially with the worship of Halone), but there's no specific ability set around to use -- it could do anything you're willing to shoe-horn in. Would be a lot of shoe-horning one way or the other, though.

Marauder (tank)
Current job: Warrior (tank)
Available mechanics: MRD has no unique mechanics
Present ability set: Hate generation, health drain, debuffing
Possible jobs (DPS): Berserker, Dark Knight, Viking, Beastmaster
Possible jobs (healer): None
Notes: MRD is also ill-suited to becoming a healer. There are a few axe-wielding DPS jobs which could be used. Berserker used axes in 5, and MRD already has Berserk. However, that would be thematically-unusual given that WAR's entire schtick is unleashing one's inner beast. Dark Knight would be appropriate in that it would take advantage of MRD's self-healing mechanics. Dark Knights also use axes on occasion, though it is technically not the iconic equipment (which is sword and board, like GLA). Viking is a long-dormant job with no specific ability set, but also really doesn't particularly justify its own existence. Beastmasters used axes in 11, and there's no technical reason you can't add a pet like X-2. You don't even need more than one pet as a healing pet would be unbalanced and a tank pet would be superfluous. Another pets job would be kinda lame, though.

Lancer (DPS)
Current job: Dragoon (DPS)
Available mechanics: LNC has no unique mechanics
Present ability set: Kitchen sink approach to ability selection -- some DoT, some buffs, some debuffs, a ranged attack, an interrupt, and a few defensive abilities
Possible jobs (tank): Templar, Samurai, off-the-wall whatever
Possible jobs (healer): None
Notes: Not many lance users in FF. Lancer has an ability set that looks remarkably similar to Marauder, making tanking actually pretty feasible. You have the a very similar interrupt (20s CD on stun), readily-hijacked main combo, and a ranged pull. It can even wear some tank armors. All you need is better AoE enmity generation and some more cooldowns. Only question is who should do the job. Templars would have a lore reason to exist, but would also clash with Dragoons -- DRG are already aligned with Ishgard, making a Templar choice feel strange. Samurai could work, but would be unusual for FF (usually use katanas) and would have no particular place in lore. You do have the cherry blossoms from Chaos Thrust, however, as well as an innate parry focus. Beyond that, you can dig up just about anything and make it a tank -- Edgar the machinist, Mog the geomancer/dancer, Kimahri the Blue Mage, or whatever suits your fancy. Whatever it is has to be comfortable with a sparse ability set, however, so Blue Mage and Geomancer are not likely.

Pugilist (DPS)
Current job: Monk (DPS)
Available mechanics: Greased Lightning, forms, Fists buffs
Present ability set: Mostly damage, several DoTs, form-based restrictions, a healing buff, a limited silence, a limited stun
Possible jobs (tank): Berserker
Possible jobs (healer): Dancer, White Monk
Notes: Not as well-suited to tanking as LNC. Lacks a ranged pull, awkward AoE enmity (would be restricted in use due to connection to interrupt), awkward rotational needs for enmity, stun is not good for tanking and comes pretty late. Technically can work, but it's not as simple a transition as LNC. Could go the Berserker route there, building a high-HP tank with evasion as primary mitigation (soak up big hits, evade to reduce healing need where WAR boosts healing and PLD mitigates a percentage). Needs a lot of abilities out of somewhere, though, and gear isn't a good match. Would also be a bit odd with MRD having Berserk and the Berserker lacking it. Anyway, PGL is the only physical DPS I can see changing into a healer, hijacking Greased Lightning and Fists mechanics to boost healing. Doesn't have a huge number of abilities for the task, however, and you'd have to invest a lot of your ability slots checking necessary boxes. Dancer is one possibility, though you'd be hard-pressed to find the slots to do the Dance portion justice without replacing some current abilities. White Monk is another possibility, but it's not exactly iconic and wasn't much of a healer in its two appearances in the TA series.

Archer (DPS)
Current job: Bard
Available mechanics: Bloodletter cooldown reset
Present ability set: Heavy on DoTs, off-GCD abilities, plus the awkward placement of Swiftsong
Possible jobs (tank): Ranger (?)
Possible jobs (healer): Devout (?), Oracle (?), Dancer (?), whatever you feel like throwing on here
Notes: Whatever happens with ARC, it's going to suck. Ranger is obvious, but it's really a DPS with little differentiating it from BRD. Being a ranged tank would be messy, especially with ARC having abilities for creating distance rather than closing it. A pet tank wouldn't do anyone any good either, given how pets work in ARR. Being an archer healer would have some precedent, but would generally just suck from ARC. You could point to Rosa from IV, but she was a White Mage, and Archer lacks anything remotely appropriate for healing. If you tried to hijack Bloodletter, you'd be stuck at the mercy of RNG for whether you are able to heal at all, not to mention how late that comes. You can do something with Swiftsong, but one ability won't get you far. Whatever ARC does, it will be bad. Another DPS with nothing differentiating it from BRD, an awful shoe-horned healer completely rewriting core abilities, or a disaster of a pet tank. Pick your poison.

Thaumaturge (DPS)
Current job: Black Mage (DPS)
Available mechanics: Astral/Umbral cycles
Present ability set: Nuke, Nuke Harder, Nuke Bigger
Possible jobs (tank): None
Possible jobs (healer): Time Mage, Sage
Notes: Ill-suited to tanking in general. Would have to make several abilities superfluous (Manaward, Surecast) in order to acquire basic functionality, and others would be rendered purposeless (Aetherial Manipulation). Astral/Umbral is a poor mechanic for a tank, since your enmity and damage would be tied to your survival mechanic. Seems much more likely that the cycling would be used as an infinite-MP healer whose weakness is in the limitations of healing duration. Not really that hard to do, but would need to still realistically need to hijack a few ability slots to meet needs.

Conjurer (healer)
Current job: White Mage (healer)
Available mechanics: None -- White Mage is as vanilla as they come
Present ability set: 5 single-target damage abilities, 10 healing-specific abilities, 8 healing-specific traits.
Possible jobs (tank): Morpher (?)
Possible jobs (DPS): Oracle, Geomancer, Seer
Notes: CNJ can't do anything but heal. Just look at the ability set. Nothing tank-appropriate, very few DPS abilities. You have two choices: dump in a cheap mechanic that completely removes all abilities (e.g. Morpher/Shapeshifter) or ham-handedly steal all of your heals and turn them into something different. Having the remnants of Stoneskin, Raise, and Protect wouldn't kill you, but having Cure/2/3 + Medica/2 + Cleric Stance would be a disaster. If you take the Morpher route, you can go ahead and do anything, like tank, but then you're not much of a Conjurer at all. It would be a pretty extreme step, and not really likely. The alternative is just to replace all of your heals with attacks or something of other specific utility. That's not exactly good either, but you don't have much of a choice. Turn Cure into Dia, Medica into Quake, add Water spells, and call the job whatever you like.

Of the popular jobs, I don't expect to see with present classes, I'd say Thief, Ninja, Red Mage, and Blue Mage are pretty hard to do. None of them work remotely well.

//EDIT:

It is possible for Ranger to be Archer's 2nd Job. Jobs are not based on their Main Stat choice but what kind of Role and skill they provide. Bard may use DEX for their main stats but they focus on being a Hybrid of DD and Support switching between these two roles depending on the situation of a fight in FF14.

That is simply not true. BRD is not a hybrid, it's a DPS. It doesn't tank or heal. It provides utility, but that is not unique to BRD; LNC and PGL provide debuffs and interrupts as well. BRD cannot somehow coexist with another job that spends 99% of its time doing the exact same thing and which is built the exact same way with the exact same equipment and exact same stats, not to mention the absurdity of "balancing" two jobs like this.