My wife and I were on the Royal for the first time last May from Athens to Southampton (12 days). Previously been on Star (Mexican Riviera) and Ocean (Alaska).
Sure she doesn't have the many options of the bigger ships but as many others point out you get a more personal service and a real sense of class. The main dining room cuisine was outstanding - every day! By far the best quality and service of any other dining option we have had on Princess!
The cabins serve as a living room during the day with sofas and extra space, and then (if you ask/tip your steward nicely) you come back from your wonderful dinner and they have been converted to a double bed - great stuff!
Sure some of the cabin fittings are a little dated, in fact I have never seen such an old fashioned TV remote control! But such things (as long as they function OK) are not a priority for us.
Overall I believe Princess are using clever marketing by having their least equipped, yet classiest ship visit the most exotic and interesting World destinations, knowing that a loyal following will go with her.
We are very, very lucky to be able to combine air miles with our next trip- Royal Princess again to Antartica on Dec 19th. Can't wait, 24 days of that cuisine!
My advice- try her and see what you think- we love her!