Has SE screwed itself?

[Sylve]

But they really really are easier.

New Job entails:
Creating 5 new abilities and their animations
Adjusting some class abilities (no need to modify all of them)
Create 5 quests and a storyline

New Class entails:
Creating a new weapon type which requires new base animations.
Creating 17-18 new abilities and their animations
Creating 1-2 new jobs (5-10 new abilities) and their animations
Balancing 11 new traits
Create 9-10 class quests and storyline
Create 5-10 job quests and 1-2 storylines

A new job does not need to be similar to the base class either. Again with ACN/SMN/SCH. The role they gave SCH is nothing like the role they gave ACN/SMN. They even changed SCH substantially from how it is in other titles in the series. It never once had pets/fairies and was only given healing magic roughly half of the time and even then rarely could function as the sole healer. They've usually been and played better as a debuffer or damage dealer (similar to how SMN is now). On that note, SMN also has taken an entirely different approach than it has in the series.

Here is where your argument falls flat.
They would need to come up with a way to change an existing class, to become something new. So you are automatically limited by what the existing class uses. The existing skills would need rebuilds anyway, since they need to fill a different role now.
I'll use Conjurer as an example here.
Conjurer gets 2 Damage spells, Stone and Aero. Yes, we have Stone II and Aero II, but its basically the same thing. In order to have the Conjurer gain a DPS job, the 5 new skills gained from the Job would have to be main rotational buttons, or your brand spanking new DPS Conjurer Job is spamming Stone II. Sounds fun.
So ok, you have your 5 new shiny buttons and have 7 DPS spells now, awesome! Except for one thing. You still have access to virtually every spell a WHM uses to heal. So now you have a DPS Job that can heal almost as well as a WHM, and has all the traits of a WHM.
Nope, cant even use a SMN or BLM as an excuse here, because spamming Physick won't get you far. Since you would have Medica, Medica II, Cure III, Graniteskin and every other tool a CNJ has without becoming a WHM. You would also have Cleric Stance.
Oops, can't use that in your new DPS Job, a blanked out button, something we currently do not see. No Job prevents the use of a skill gained from its base class. And what happens when you try to do Sastasha -> Toto-rak runs? Congrats, you may spam Stone / Stone II from start to finish. Exciting stuff.

Any new jobs to be attached our existing classes NEED to be continuations of what the base class currently is. Otherwise, You're trying to make unique jobs out of half a class. It wont work and will feel awkward and bland.

The Archer is a class i can see getting a new Job. Sniper, no songs except that learned as an Archer, with a very heavy focus on dealing big burst hits.

I would very much like to see more multi-job classes, If only because i like variety.
But i do very much feel that any multi-job classes should be created new, from scratch, to be multi-job, the way the ACN was.