The best advice that I, or anyone else, can give you is: Get a TA who specializes in group cruises.
There are amenities and price reductions for booking eight or more cabins plus booking and coordinating a large group can be a nightmare. It is something I wouldn't do and I am fairly knowledgeable about pricing and cruises.
One thing to keep in mind. You will need one adult (25 or older) in each cabin.
If you need a recommendation you can PM me and I will give you one.