What if Classes were Jobs?

[ADVSS]

Well a while ago I had come up with a very similar system in my head for what if they had kept the cross class system, added jobs, but threw it in a ff11 esque blender. after creating some obscure number of "prestige jobs" i figured 70 sonething would be way too much
it did, however cover every single niche possible, from turning a fighter to paladin or darkknight, to turning a darkknight into a deathknight(necromancer knight). The idea is very similar to OP but maybe is a bit more extensive, like 7 dow 7 dom and the ff11 thing would be like every 10 -15 levels you add a new "class" onto the spec, eventually having knights that can use xtype of magic, etc.
By new class you can choose to go to another class to learn it too or just get mastery in a higher tier of the same class, granting abilites like dual wield, heavy shields and armor, etc. when enough mixing was going on you would get some prereq "job abilities" that related to your path of mixed classes.