As you point out, Celebrity is suffering from trying to be all things to all people. That needs to end and Celebrity needs to find their niche (much like NCL has found their niche). With as many berths as Celebrity is sailing with today, I do not think they will be successful. They need to sell some of their ships and develop a dedicated nucleus of cruisers.
Actually, my impression is that Princess Cruises has been far worse than Celebrity Cruises in trying to be all things to all people. Royal Caribbean Cruises Ltd. (NYSE: RCL), the parent company of Celebrity Cruises, has another cruise line -- Royal Caribbean International -- that's positioned at the top of the "mainstream" segment. Celebrity Cruises would hurt its sister line by lowering its standards too much.
If anything, my impression is that Celebrity Cruises has developed an image of trying to be more "upscale" than the other "premium" lines -- though I'm not sure whether and to what extent it really is. The most recent changes -- for example, a category of standard cabins that offer the amenities otherwise found in suites, undoubtedly for a premium over the fare for a standard cabin without those amenities -- seem to be aimed at moving things more "upscale" rather than restoring what once was. These changes will enhance such an image.