Well, getting 2~3 classes at 50 by the time 2.0 rolls around shouldn't be too bad, there's 7 battle classes after all!
And well, the thing about the Main Quest is that... Right now, the end of it at L50? It's MORE OR LESS what you'd expect to be the point where you first meet Exdeath in FFV, it is quite literally the beginning of the story and first introduction of the villain.
The 7th Umbra Era content, mind, have a far better growth and expansion of the villain and store and is far more 'complete'.

So there should be, in fact, quite a bit more story in 2.0.