This is pretty good. I'd eliminate the Icebreaker, though. I hate Icebreakers about as much as I hate stupid, unnecessary meetings.
I might eliminate opening remarks, as well. I like to 'get in and get out'; especially if there's a lot of 'business' that I need to cover in the meeting.
Yeah, I'd say that the only thing you HAVE TO HAVE in a business meeting is opening and closing prayer, and a discussion of the business at hand. Everything else is optional.
For me, icebreakers can help ease any tension or anxiety folks might be feeling, or change a negative attitude into a positive one, or just make people laugh. In this type of setting, I wouldn't recommend taking more than 5-7 minutes total to do it, and if you can do it in less time than that, that's even better.
An icebreaker is especially helpful when you are dealing with new people (or a totally unfamiliar group of people, which is usually what I'm doing), or when you have dissention within the choir. Folks mad at each other or not getting along, etc. (Karl, if you want some ideas for icebreakers, let me know).
As for opening remarks, I'd definitely consider that optional, too. But, it's another item that doesn't have to take long. I'd say 30 seconds to 2 minutes is sufficient to thank ppl for coming and tell them why you called the meeting and what they can expect over the next 45 minutes.
But again... all that stuff is optional, so it's best to go with whatever works best for you and your group.