"The silliest thing, to me, is submitting a CD and wanting constructive criticism in return. The time t seek constructive criticism is before the final mix, not after the release."

Next time I'd like to find a good mastering engineer to do exactly this, mostly for what I could learn from the experience. Not one that just feeds it through a Waves L2 and hands me the bill, but one who listens and gives advice, and who I can watch and hear at work.