That looks awesome!
I'm not at all familiar with the requirements for this costume, but to me, it seems like some light weathering might be good. It'd give it a bit more of an authentic, worn, I've-lived-as-a-hermit-in-the-desert-for-20-years, type of look. Costume requirements permitting, I'd rough up the edges and areas that would naturally wear and tear with some sand paper; tie the material up in knots to put some wrinkles in it; maybe give it a light dusting with some dry pigments.
Then again, there's a reason for me being a TD...Others may not enjoy weathering stuff as much as I do.
Best of luck with your application!
At this time, a friend shall lose his friend's hammer and the young shall not know where lieth the things possessed by their fathers that their fathers put there only just the night before, about eight o'clock.
-Book of Cyril