You should only need one copy. It should have the entire booking (all the passengers traveling with you) unless you booked more than one cabin. If you got multiple sets of cruise docs that contain the same booking #, bring the most recent (as any cabin number changes/updates will be in it)
Do you need every page? No. The Set sail passes and hotel/transfer vouchers, yes. I would also take the pages that have your cabin assignment information on it. Then your passports and the credit card you want to use to back your charge account with on the ship.
I don't remember how much "fluff" is in the cruise docs for RCI. How much is left after the "important stuff" above? To be safe, I would bring any pages that have information unique to you and even then you probably won't need them, but better to have them than not.
Once on board, I do a thinning of documentation. You don't need anything but return transfer/hotel vouchers and return flight info. The rest can be tossed if you like. (My wife likes to use some of it for scrap booking fodder) The one thing I always seem to forget is my return flight information. I am always careful to have all the information for my trip too the ship (because that is the thing I am most concerned with getting correct.) But when its time to come home, I always seem to realize I thinned that page out of my folder or forgot it completely. Then I end up in the internet cafe looking up my flight info...
Carnival Cruise Lines:
Fantasy 90, Celebration 95, Victory 05, Conquest 05, Spirit 6/06, Freedom 6/08, Holiday 7/08, Victory 6/09, Valor 9/09, Dream 6/10, Splendor 8/10,Conquest 8/11,Magic 11/11,Triumph 4/12,Spirit 7/12,Freedom 11/12, Triumph 2/13 - The fire cruise
NCL Dream October 2006, RCCL Mariner OTS June 2007