There is no reason to play after the story. And even then - in the story you don't matter. There is no reason for you to do anything. Then throughout the whole game - If you do this - it could be worse so don't, but you don't really have a a choice. You cannot pick to do anything, there is the main story, they way they want you to do it - and that is it.
I felt and feel like - why? Why am I doing anything, why? I am not invested in my character - and they REALLY make you feel that way with how easy it is to change everything.
And that is besides the crazy skill tree of pain. Use a template or you will be MUCH weaker. It is a must.
It was fun to play though the story, but I find I am now done with it.
Worth the money if you have it to spend. If your debating to get this or something else - get the other thing.