That's just lore. Otherwise it's just all the same.
Ancient magics are just like normal spell except longer casting time and piss poor damage compared to MP cost.
Blue mage spells are just spells, except the way you get them from monsters and how you allocate them. You have the damage spells, the healing spells, some utility ones and that's it.
Ninja is not the best evasion class because Thief is the one with more evasion bonus traits. And everybody had the utsusemi.
If you are talking about melee DPS in FFXI, everybody is just in autoattack while waiting for TP to do TP attack
