I actually wrote a blog awhile ago about thoughts I had in regards to the class/job system and what I'd like it to be. Mostly just brainstorming and wishful thinking.

But one of the main premises I came up with should be that the classes should really only be defined by the weapon they carry and in creating jobs you'd need a mix of several classes. So the classes really become less defined and more amorphous, but when you unlock Jobs it's the jobs themselves that really define the roles of the character.

In which case, classes like Gladiator and Marauder would need to be simplified and basically become Swordsman and Axeman, with Gladiator and Marauder maybe being retained as Jobs. (though I did mention Axeman only because I really couldn't think of anything that sounded more refined.)