I love the differentiation with the limit breaks between the different types of players, but I would love to see each class get a slight variation. The current LB's could be kept, but assigned to specific classes, allowing others to get different skills. This could further lead to the reason why you would pick one class or another for a given instance, and give more a more unique spin on each role.

Even if this was simply "graphical" in nature and didn't change much else, it would still be a benefit! Though, it would be great if they actually had slightly different mechanics.