Why did SE decide to make the three new classes not require base classes?

[EdwinLi]

Unfortunately, right now the stories surrounding class-job separation is the only thing keeping SE from dropping the established classes.

The class guild helps us to step into the world and city it is based in, and there is nothing saying the story surrounding the new jobs won't do the same for Ishgard.

Well best we can tell now these new Jobs may have the same requirement as Rogue unlock, being require lvl 10 to unlock Armory for new characters.

Not to mention their location is unknown and being Jobs these new Jobs may not have Guilds in a City State like the classes so the Job Trainer location is most likely out in the world or in a specific location.