A difficult one as an editor you have to make decisions as you go along. You do your best but the whole process is live and is normally uncontrollable. Having said that a good seasoned Videographer should now the ropes and be able to make the best of the situation that arises.

I do talk to the client about re-work before the booking so they know where they stand, any errors I will fix FOC, anything subjective is not normally done as it is subjective and if i have made something red and you like blue, sorry, if there is something that is embarrassing then I will look at it.
The fix, does not normally take that long, but its that dam 5-7 hour render, re-authoring the DVD and burning and printing a new disk that takes the time.

I tend not to use music during the photo session in my weddings apart from the titles at start/end, montage in the middle and the high-lights at the end, mainly because I like to make the wedding interesting so it does not require that music to make it more appeasing.

As for how much for the master, your guess is good as anyone's, all depends on what he/she thinks they are worth.

Good luck and do keep us informed.