Wow, shiploger, that is really a hard one
The Island Princess is a great ship, So have been the Holland America ships we have more than 100 days on -- and the Crystal Harmony was wonderful.
But I think I'd have to give the nod to the old Crown Odyssey, then of the former Royal Cruise Line. [Now the newly refurbished Balmoral with Fred. Olson Cruise Line] We took our first two week cruise on her in 1991 from London to St. Petersburg and back, and since it was our first real cruise, there was something magical about it.
Then years later, when she was under the 'Orient' flag, we cruised on her again from Auckland New Zealand to Los Angeles, clear across the Pacific. A wonderful cruise
So she'll always have a special place in my heart.
But then, like many others, we are now addicted to balconies/verandahs and so it would be hard to go back to the old Crown Odyssey.
In a couple of weeks we'll be going on our first mega-ship, the Crown Princess -- maybe it will turn out to be our favorite.