Kudos for buying the tux. Rentals are, imho, without class.
I didn't care that much, so let the MIL have free reign, but at the wedding couldn't help but think how much nicer it would have been for the groom to be in his own clothes, and ones that, y'know, fit. And that weren't so threadbare, actually quite shabby to a textile geek like me. My choice would have been a decent morning suit for the groom, and whatever they wanted to wear for the attendants. Jewel tones for the women, to ensure that no one clashed too horribly. As it was, the guys were forced into horribly ill-fitting shabby tuxes, the girls into cheap pastel-ish dresses, and much money was wasted.
Of course, I think you have to go to England to find such a thing as a morning suit anymore.