Maybe I did miss some information in regards to what differentiates Class and Job this time around.

If what Betelgeuzah says is correct: Classes are tuned more for solo play, while Jobs are for party play. Correct?

With this in mind, what actually occurs is not just the presence of the fourth archetype, but a dual archetype system.

Something along the lines of:

Solo Archetypes
Tank/Damage
Tank/Damage/Healer
Damage/Healer
Healer/Damage

Group Archetypes
Tank
Damage
Support

But doesn't that create its own set of problems all together?
In order for one to be viable for serious group content, new players & old players would need to unlock and relevel a new class. At that point, isn't it just a roundabout way of doing a character wipe?