To answer your question about the mini suite, the price you see listed again is the price per person for the first two of you, and the others who join you, their fare would be less. You could then divide the total amount among you. If you go onto one of the cruiselines websites like RCI or NCL you could select a cruise for fun and check out the how the pricing is done for the 3rd and 4th persons. For any future cruises you have in mind I would go through a travel agent. The prices I have paid for my past cruises have always been cheaper that what I see posted from the cruise lines.
Century Dec 2003 Western Caribbean
Century Nov 2004 Eastern Caribbean
Monarch of the Seas Jan. 2005 Baja Calif.
NCL Dream Nov. 2005 Western Caribbean
Monarch of the Seas Mar 2006 Baja Calif.
NCL Star Oct. 2006 Mexican Riviera
NCL Pearl Nov. 2007 Southern Caribbean
Mariner of the Seas May 2009 Pacific Coastal
Mariner of the Seas June 2009 Mexican Riviera
RCI Radiance of the Seas