Starting over?

What are the main reasons you might want to start a new run? I’ve basically 100% the game at this point; lvl 80 with legendary gear and I’m still having fun don’t get me wrong. But, something is telling me starting a new run on grave walker (currently on brutal) might be fun, but I know it’s going to be a pain to get all my stuff back.

Is there really a good point to starting over besides just resetting the power balance/experiencing the story again? Because it did take a long time for me.