I'm not sure about the costume either. It's so light especially the hood. Very elderly monk like but it really needs some darker shading to give it a real Jedi feel that we remember.
I will say one thing. It looks like JJ is not costuming him like a Tattooine native. If you remember from the prequels, all the Jedis were wearing Tattooine tunics like Ben. It looked good but didn't make alot of sense. This outfit sort of corrects that.