Most cruise prices, I think, regardless of where you book, are the same. The only difference is that if you book through the cruise line, they pocket the commission that they would have given to the travel agent. I doubt you'll see much difference in fares between travel agents and RCI, once you do your research.
2007 - Majesty of the Seas (Bahamas)
2009 - Enchantment of the Seas (Western Caribbean)
2010 - Freedom of the Seas (Western Caribbean)
2013 - Golden Princess (Alaska, roundtrip from Seattle)