I think it's a little too early to tell how exactly the job system differentiate itself from the class system, but I won't deny the fact that based on the currently available information from the devs, the job system is merely an upgrade/specialization of the current class system. While this may seem lackluster, I think it's too soon to judge without being able to see the whole picture, and unfortunately only the devs have access to that, so unless they come out and give us more details about how exactly the class and job systems differ from each other, we can only wait and see how the game goes.

While I see and share the OP's concerns to some extent, given how much YoshiP have pushed the game towards the right direction in general, I think it is only fair for me to have a little faith in him and see how things unfold in the next few patches. After all, I did spend 50 bucks on what Tanaka showed me in CB. lol