Introducing the Job system for the first time, your characters here can be any role you'd like, and even change roles at any point in time, which would become a hallmark of later titles (and revised even better in FFV).
Unfortunately, the characters themselves see very little actual characterization. Only your first named character is ever even referred to by anyone, with the three others simply tagalongs. While the 3D remake fixed this, those changes are not present here in the Pixel Remaster.