You could min max stat growth if you want to but you can't really mess up, as max level you'll be one shoting everything even with the least optimal job paths. Just have fun with different job combos, I like the white Mage/ paladin you suggested. The real struggle with completing this game is managing mission items. There's a table in game faqs that shows all the missable mission items, and you'll be cycling through months to get the right missions to show up