This was our first cruise ever and we will definitely do it again after a very nice trip on the Glory.
We were in a Grand Suite, and the room was one of the two big highlights of the cruise. Although the decor is dated, the room was spacious and some of my favorite memories included relaxing on the large balcony. Although it would have been nice to have more perks to enjoy the "suite life," we knew in advance that Carnival has a more egalitarian approach. Still, we did get the VIP embarkation, which was seamless.
The other highlight of the cruise was great service. Although we did not see much of our cabin steward, it was only because he was unobtrusive and always managed to find good times to clean our room, and of course we loved the towel animals. Many of the other staff were outgoing and provided us with great service -- standouts included the East European ladies working at the Alchemy bar, our entire team of dinner waiters, and the very night club bar staff.
The food was great when we had comfort / "fun" things -- Guy's Burgers was popular even with my partner who usually stays away from burgers and fries, the new burrito stand was excellent, the deli and room service sandwiches always hit the spot, and the late-night pizza was amazingly good. (However, the buffet's dinner selection looked dreadful, and we only ate there for breakfast, which was fine.)
On the other hand, more "formal" food sometimes fell flat. For example, the Steakhouse is a beautiful room but our steaks were bland and not as rare as we ordered. Similarly, the MDR dinners were never spectacular, although with one possible exception they were not bad either. I ordered the Indian food a couple of times as a distraction from the meat-and-potatoes stuff - and it was good!
The late-night fun was well done on this ship -- I enjoyed roulette in the casino, cocktails at Alchemy (what a great concept to have a true mixology bar!) and most of our group seemed to end up at the White Heat night club, which was a lot of fun.
Only serious complaints were that the pools were tiny and the loungers were never available because of all the chair-hogging going on. And the Punchliner's Comedy Brunch on the sea days was just weird -- we couldn't even see the comedian, but at least that meant we weren't subject to his lame "so where are you from?" audience participation shtick.
We would certainly be willing to try Carnival again (for instance with a group) although it did not make converts out of us either.
One final note: We were part of a large LGBT group and felt completely welcomed at all time both by the staff and other guests.