This is basically a lost argument since the OP is an confrontational child.

Getting one class to 50 gives all the rest of your classes a nice exp boost. So fate grinding is really fast, I went from 1-35 on a dragoon in just a few hours. A leve with full bonuses gives you just short of what a regular quest would give. You want a sloppy amalgamation of repeated region quests. Leve's are short, repeatable, and require no transportation. What you want is already there. You just refuse to see it.