Great game, third favourite mainline FF probably.
Most of the classes are pretty decent. You'll probably start figuring out what the power skills are later on but there's plenty of time for that. Avoid Berserker (-except- possibly for a quick Vitality mastery, but only do this against a few specific grind spots), otherwise all other classes are quite useful although Dragoon comes pretty close to lacking a point (it's not -bad-, though).
Freelancer/Mime are your ultimate destination classes no matter what. They'll have the stats of anything you master + all your learned passive abilities.
Have fun!
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