its really difficult to give a general overview, because no two ships even in the same line are the same, they each are unique in their own way. Your cruise choices depend so much on what you want to do, what you personally want out of your cruise experience, if you could give us some more details we could give you some specific advise
If you go to the home page of CruiseMates, and click on Princess Crusies, it will give you an overview of the cruise line. I think it's a good place to start, and you might find some of your answers. Happy Cruise.