Forgot to answer this part:
Quote Originally Posted by swordrain View Post
And now that physical levels are gone, is there any advantage to leveling multiple jobs/classes on a single character other than more versatility?
Yes. Very much so. Each class has some abilities that are exclusive to that class, and each class has a few abilities that can be equipped on other classes. Most classes have at least one low level ability that will be really helpful on other classes. Level Conjurer until you get Cure, Protect, Stoneskin, and Raise. Level Pugilist until you get Second Wind. Level Marauder until you get Bloodbath. Level Lancer until you get Invigorate and Feint. Level Archer until you get Hawk's Eye. And then you can equip those abilities on any other class, and they'll make your life much easier.

In that way, the game encourages everyone to level several different classes. It helps you be more versatile and well rounded.