Most of the games with in battle party sizes of 3 usually have everyone as jack of all trades which makes the battles more boring to me compared to job classes both predetermined and free choice.

VI was the only one with a 4 party jack of all trades crew, but not exactly as everyone had something that made them unique unlike in VII, VIII, and XII. I haven't played XIII yet so I don't know. I have a hunch that they're jack of all trades too.