I don't cruise that frequently although my first
disney cruise was in the early 2000's so I've been cruising for a long time. When I decided I wanted to do a cruise for my upcoming 50th birthday I looked at Disney first. I just wanted a "vacation" - relaxing and not very expensive plane tickets and I live on the east coast so Florida is usually pretty reasonable to get to.
I had a choice of the Magic 5 night out of Ft Lauderdale or the Fantasy 7 night out of PC. The Fantasy is the first real trip to
lighthouse point so it was already quite booked up and very very expensive. The magic I ended up paying around $4700 for a secret verandah room for 2. Then I started shopping around to see what else I could get for my money.
I am very picky and I like nice hotels, so an older, less well maintained, not as beautifully appointed ship would not make me happy. I found that when comparing apples to apples - nicer
Royal Caribbean ships (not the HUGE new megaships but still nicer ones) or other cruise lines upgrading to similar amenities that Disney provides as a base for their standard balcony rooms, there wasn't much price difference. Sure, they were much less than the $9-10k it would have been on the Fantasy but compared to the magic, not much difference. I like the 5 day itinerary for an adult only trip as it allows time at both ends to deal with stuff at home.
And I just love the magic, it makes me feel good, it is familiar, I don't have to "learn" the deal with another cruise line and it is an absolutely beautiful ship that makes me happy to be on it. I loved the fantasy and dream too and had the itineraries worked out would have been happy to have been on any of the trips. I get that the special and desirable voyages will carry a huge premium but if you just want disney for the sake of disney there are options and if you compare apples to apples against ships that are comparable (It seems Disney is the only one where all of the ships are kept up to snuff - in other lines you really have to make sure you're not on an older/dated ship or if you are, that accounts for lower price), the pricing is really not all that different.
If you are willing to go down a step then of course you can save money. If you want a particular itinerary that is not one of the standards, you can save money as these are things other cruiselines have been doing for a very long time (I have heard and read that princess has Alaskan itineraries pretty much nailed.) But if you like Disney for Disney's sake there are options and if you are fussy about being on a nicer ship then the differences are not really that great. You are going to pay for nice/new/well maintained/great customer service no matter where you go.