A great experience can be had on any cruise ship for any cruiseline. I have been on 6 Carnival, 5 RCCL with number 6 scheduled for next year, 4 Princess, 4 NCL, 2 Disney and one Celebrity. My cruises have ranged from a 3 night
DCL cruise to several 14 night Princess cruises. My itineraries have included the Caribbean, Bahamas, Canada, Alaska, Hawaii, Mexican Riviera, the Mediterranean, the Baltic Sea, and British Isles.
At no time do I compare any of the other cruiselines to Disney as to me I do Disney in order to have a Disney experience and not really for the itinerary. I like all the cruiselines for different reasons and the truth is there are pluses and minuses with all of them including Disney. The food to me is pretty much about the same on all of them. I truly love a Disney experience, but I can go on a couple of Carnival cruises for the price of a
Disney cruise and since I like to cruise a lot, I'm more likely to go for the cheaper cruise. I rarely drink on a cruise and I sail Carnival. I honestly don't see any more drinking on a Carnival ship as I do other cruiselines.
A cruise is what you make of it. No two ships and no two cruise experiences will ever be the same, even on the same ship (variety/number of cruise activities, cruise staff, food, etc. all change). You can't judge a whole cruiseline by one ship and by one cruise experience. For me when I am looking up a ship online, I look to see how well-maintained it is as I've been on a few that weren't maintained and didn't care for them; I have been on a ship both when it was new and when it was old and loved it much more when it was new. I really like how when I'm on a Princess ship they are always cleaning/polishing it up. I love the beautiful RCCL Jewel of the Seas which I went on in April and it kind of made the DCL Magic which I went on in August look old. Btw, one of my favorite ships is the Carnival Glory, it is not gaudy or Las Vegas looking at all, and it is well-maintained. I've been on that ship twice to Canada and would say both times there was a nice group of passengers.
I've been cruising since I was 14 and my first ship I would still consider one of my favorite cruises (and one of the best food experiences I've had on any cruise), the NCL Starward which was under 20,000 tons. Cruising has changed a lot since then, some changes I've liked for the better and others not so much. But I don't think you can beat a cruise and so I will continue to keep on cruising regardless of the cruiseline.
If having a Disney experience when you travel is a must, then save for the Disney cruise. If having just a good cruise experience is all you want, then it can be found on any ship with any cruiseline. Figure out what you are most interested in (such as length of cruise, itinerary, cost, size of ship, "freestyle" vs. set time dining, ship features such as a skating rink, room size, age of ship, etc.), and then pick a cruise that seems to fit what you are looking for.
Have fun no matter what you choose.