Well, as of right now, I know Magi are sort of that type - though it's less about planning and more about in-battle tactics. Technically, any character can be the planning type. What do you think officers do before going into battle? Plan strategies and tactics. However there's only so much you can plan for... ^.-

I suppose there might be alchemists? Though potions would take time to have an effect and they would give the user a noticeable, but not extreme advantage over their enemies, like quicker reflexes, temporary strength - you could have a character that needs to plan in that sense, if you're really set on it. ^^