I have no loyalty to anything. Does that sound awful? Well, actually I have loyalty to Crest Toothpaste and that's about it.
Where cruising is concerned, I'm inclined to go with either one of two things ... the itinerary or the entertainment. I wish ALL the cruise lines would offer more detailed information on their entertainment so that I could then make choices as to what shows I want to see. The first line that does that, that has stellar entertainment, would definitely see my loyalty.
I belong to EVERY airline mileage program. My loyalty to the airlines is who has the best fare with the least amount of stops. I use my miles for free trips instead of upgrades and usually get at least one a year. I pay for First Class when my client's budget approves it which I love because then I really rack up the miles!
If money were not an option, I would probably have a loyalty to the higher end cruise lines ... Crystal, Silversea, etc. The company that gets my business is the one that delivers the best product, not necessarily the cheapest or one that offers the most volume.
I don't need to feel like a VIP though. That may be why I have no particular loyalty to any one company.