Exploration

[Wilan]

I was thinking of Thief (basic, you steal small things) > Pirate (advance, you steal big things.)

Pirate isn't really a FF job. Something like Class Thief > Job Ninja makes more sense. As a thief you're sneaky, use (dual wield?) daggers, hit from behind unseen (speaking of battle, of course), then you master it, you use shadows more and more to your advantage, and some old master decides to you're worth passing on the dark arts of assasination.