Easy, start acting like a premium line. Now, I sail Radisson exclusively. At some point, I know I will want to venture to other ships. Celebrity seems to be the most likely choice. 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.
just my two cents,