We literally just got back from a wonderful 7 night cruise on the Disney Fantasy. There is so much for kids to do. This felt like Disney world at sea. We felt like we were going from one event to the next. It can get exhausting. Characters are everywhere.
Our kids loved the Oceaneers Club/Lab. They always wanted to stay longer or go back after dinner. There are numerous counselors and activities.
The pools are tiny and crowded except at night. If you want to swim, forget about it. The pools are nothing more than an over-sized hot tub. They really need more pools. The adult pools and decks were never crowded. My wife booked a spa treatment, but they were offering so many specials throughout the cruise that booking ahead did not seem necessary. This may not be true for all cruises though. The AquaDuck was nice. Pretty busy during the day, but no lines at night.
The fitness room was very nice. Top notch equipment and ocean views.
Dining- we had breakfast and lunch at Cabanas almost everyday. The food is very good. Lots of seafood and steaks. The dinners were good as well. We had the first seating at 5:45. The service is impeccable. They wait on you hand and foot. I think we would do the second seating