Question for the "bigger" bridesmaids?

Here's an idea - Instead of being all matchy-matchy in the same dress, why not just tell each of the girls to go out and buy a grey/gun metal/smoke colored dress that they love (grey is very in this year - it's the new black) - they shouldn't have any problems finding something. That way every girl will be sure to be comfortable in the dress that they've picked out.