Dual Role Classes

I love the idea of each class having two roles like arcanist and I think SE missed a huge opportunity with other classes.

I think each class could have dual roles and each of these job sets should be a lot closer intertwined (except xp. They should definitely have separate xp bars). For example cross job quests. Once you get both jobs to a certain level, say every 10 levels, you get a quest that involves both jobs and the stories cross paths.

And say in a dungeon and your tank leaves midway, you could go back to the start ring and change to your paired job, of course the party would all have to accept and you couldn't leave if you didn't meet requirements, then just need to worry about getting a Dps replacement.

It seems there's a lot of missed jobs that would be hard to implement because there's a job that's similar already like them such as thief and ranger.

Of course a lot of adjusting would have to take place such as moving abilities from class to job or vice versa and I'd like to see new armour types and weapons such as one hand spears. Hearing of SEs plans to do away with one hand staves and such makes this idea harder to make work as well...

Some of the pairings I've thought of are as follows. I've thought a lot about these jobs and their roles but I'd love to hear other suggestion :)

Gladiator: Tank - Paladin
Dps - Red Mage: cloth or leather armour. Closer to what bard has and not robes. Has a good balance of melee attacks and ranged magic.

Pugilist: Dps - Monk
Healer - Dancer: tp based heals. Maybe mp spells to restore own tp and such. Mostly effects take place around Dancer but would definitely need long range cures and esuna.

Marauder: Tank - Warrior
Dps - Beast Master: I'd really like to see berserker here, but I don't think that could work as it does in other FF games in 14 plus it seems the warrior story is pretty berserkery anyways. Beast master would be a pet job with several pets. Work similar to summoner but melee.

Lancer: Dps - Dragoon
Tank - Legionnaire (something similar): uses same scale mail as dragoon, a one handed spear and small shield. Focuses on counter attacks and blocks and parries. Balance might be an issue but I'm sure SE could figure that out

Archer: Healer - Bard: would work like dancer except with songs
Dps - Ranger: like bard is now, but no songs.

Rouge: Tank - Ninja: I loved nin tank in FF11 and was very disappointed to find out it was going to be a Dps in 14... Same equipment as now. Would have to implement more focus on evasion as a stat. Would need to get shadows. Maybe a few abilities, like the flash equivalent, give a stack of shadows to block enemies skills ( not auto-attacks. Otherwise they'd be going far too quick unless there's a way to refresh them constantly) would require a lot of balance to make it work...
Dps - Thief: gets the steal, sneak attack and trick attack. Very positional like sneak attacking behind target and trick attacking behind tank like 11

Conjurer: Healer - White Mage
Dps - Puppet Master: wasn't too sure about this one. Pup was a hoot in FF11 but I would like to see something unique. Not just another pet job.

Thaumaturge: Dps - Black Mage
Tank - Mystic Knight: this one gets me excited :) would have a one handed wand/mace and shield, would wear plate armour. All existing spells would become physical elemental attacks like Steiners in FF9. Blizzard 2 and fire 2 could become the flash equivalent and you'll still use mp and dance between astral and umbral.

I know this would take a horrendous amount of work to balance but i love the feeling that summoner and scholar are so similar but a few key differences make them completely different jobs. I'd love to see that relationship become closer and I'd really love to see it in all the classes, as well as pretty much doubling the amount of jobs and allowing a lot of missed jobs to come into Eorzea :)

Umm.... But the shared XP bar is literally the only good thing about the current branching job...

Some upsides with multiple jobs per class are:

Possibility for more jobs with weapons similar to the ones we have now.
If all jobs are disconnected then to introduce another job that uses bows then you would have to create a new specific type of bow that is unique to that job.
This doesn't work as well if the jobs have different roles though since the main and substats might differ.

More jobs implemented overall since classes to build upon already exists.
It probably takes shorter time to build a job on a class that already exists than to create a new class and job with all new abilities.

Downsides would include the risque of the jobs feeling way to similar unless done right and lack of investment as a player if you already have the class at max level and only have to do the job quests.

I would love if they could at least make it so that adding more jobs to existing classes is a possibility in the future. It is always nice to have options when creating new jobs after all.

That being said, I think they're going all in on only making new jobs that have no connections to the existing classes since that's what they've said that they will do.

For balance reasons, they likely will never do dual jobs again.

And based on what they did for HW, I doubt there will be any future "classes" either, only jobs

They won't do dual role jobs again since you effectively can level 2 jobs at the same time. And to pad out their game they will separate each job individually so you have to level from 30 to 60 or whatever the current cap is for each one.