I do like that classes/jobs are defined by weapons though, as for cross class skills I couldn't care less about them.
That's one of the two things about it that I didn't like, that and being able to use any WS regardless of weapon.

I always felt they should redefine class from "Sword user" or "Spear user" or whatever, and choose independently what classes can use what weapons (a long with linking WS's/combos to each weapon), such as in FFXI, while giving each class abilities exclusive to them and abilities that can be cross classed.

But here's what I don't understand. Jobs are supposed to be more defined roles, but classes are VERY defined as it is. Gladiators most damaging attack doesn't let them deal much damage as they would need to, in order for them to ever be anything but a tank. LNC and THM are in the same situation as a Damage Dealers. There is currently no way that Lnc could really do anything other than deal damage. They can't be a primary healer or be a primary tank, all they can do is deal damage, and THM crush the enemies with nukes. How are jobs supposed to be more defined than that?

In order to have classes and jobs coexist in this game, they'd have to make all classes excel at nothing, and be the jack-of-all-trades, while having jobs the specialists. Or possibly have classes as being base templates for jobs, but there would be no point for that unless each class has multiple jobs tied to it.