Bob,
I am not sure about the 1/2" and 5/8" argument.
And concerning the double doors...you should really take your wife on a nice romantic dinner, set up some candles for her to take a bath, and after 15 mins in the bath mention to her the double doors because this will complete your soundproof room. If you don't have double doors it will be the weak link in your room.
Regarding the MLV in the ceiling.
Go here and read up on the tripple leaf effect. It may have an effect with MLV, then RC, then Drywall. Read that page anyway because it has alot of info on double studded walls.
