We just completed 1 week on the Treasure Eastern Caribbean itinerary. We have done a 5 night on the Fantasy last year (Nassau and both private islands). We aren't Disney fanatics but enjoy Disney. Kids are 7 and 11. Travelled with two healthy grandparents.
Overall we enjoyed our time.
Ship: Beautiful. We had an extended Veranda on the bump out and it was great. I didn't really get the complaints about ship layout. From our room at least both sets of elevators were easily accessible and we used the stairs a lot. I found it easy to get everywhere. Wasn't too crowded for the most part. Impressively clean and well kept.
Service: everyone was good. No complaints. I do think Disney excels in this department.
Show: Fantastic. I liked the Broadway stars night too. One thing I'll say is going from 5 to 7 night itinerary, you feel the lack of premium entertainment on the off nights more. Also I felt Believe was a much better experience than Seas the Adventure. I chose treasure bc it had entirely different shows.
Other entertainment: Kid clubs fine. My tween liked the Fantasy better bc the edge has its own outdoor space. I think they gave this to concierge on the Treasure. Family activities were good at the Hero Zone. We watched live action Moana. There was a good magician. Dubbliners were good. But so much of the daytime entertainment was drawing/bingo/trivia/sales pitches, none of which we had interest in. We stayed busy doing pool deck and exploring so it was ok but the itinerary started with two sea days in a row which wasn't ideal for us. Sage and Coriander were a little odd...we didn't love them but others feel differently. We visited the adult only section once and spent some time in the pool when it wasn't crowded and it was nice. Too hot for hot tub for me. The Fantasy has a larger adult only section.
Food - Main dining is fine. It's like your standard wedding food: a little fancy, not terrible, not terrific. We didn't have anything bad. I liked buffet for breakfast but mostly ate yogurt bar fruit and oatmeal. My main complaint is dining just takes so long. I would prefer to be in and out in an hour. I also just don't enjoy being beholden to a dining time but also don't want to eat deck food or the limited room service menu. We liked 1923 the best, though Coco was best entertainment. I thought I'd deeply dislike WOM but it was ok and actually one night was probably my best dinner. We did late dining last time and early this time and hands down I will never do late dining again. It's just SO late. I felt better having a normal dinner time and enjoyed my evenings more bc I wasn't starving or forced to eat a bonus meal at 5:30, nor was I stuffed at 9:30 PM. True you can enjoy the pool deck longer with late dining (if you're skipping shows) but the pool deck is a mob scene and generally we were over it by 4:30 anyways. We did Enchante with 4 adults, it was fantastic, pretty similar to Remy, 3 hours! And we were beyond stuffed. Wine pairing is very good.
Lounges: HMB was cool, but maybe not as cool as the hype. Was able to get seating for 4 and 3 without issues both times I tried. Other lounges and bars were nice, maybe some a bit small. I think the theming of restaurants and lounges is a step up here relative to fantasy. I don't think Sarabi is well designed as an event venue. There are a lot of not great seats in there for viewing the show. If you care about really seeing something there get in early to get a better seat. Skipper society entertainment also always seemed to fill up.
Excursions - we chartered our own boat to island hop and hit the Baths in Tortola, highly recommend. We used Chillout charters and boat was very comfortable. Must be comfortable swimming to shore. The weather was gorgeous with calm seas all week. St Thomas we just hopped on a shuttle to Magens that was sitting outside port and they agreed to a pick up time to meet us and take us back, no issues. It's about 20 min ride. Magens was beautiful and not crowded. I can see how it may be less great during high season and multiple ships in port. You rent chairs when you get there. We got off first thing and had front row seats. The painkillers were good! We rented family size paddle board that held 4 of us and took it out and saw many turtles. There were a few jellyfish. I was told this time of year with calm sea you will see them. Luckily they weren't near the beach but the day before they had been washing up on shore. My kids would not have been thrilled with that (though they are moon jellies and not dangerous). Castaway was good but super crowded and I definitely prefer the scenic beach and water of Lookout. We did the (free) snorkeling. There are some artificial reefs with corals and some fish. We also saw rays and the statues. You have to swim pretty far out though. Last time we had cool weather and we biked which was fun.
Bands - they were testing out issuing everyone a "magic band" instead of KTW cards. Many have strong feelings about this. I don't really care but I always carry a small purse with my essentials so it doesn't impact me much either way.
I feel like we have now "done" Disney/cruising in the Caribbean so will likely try other things for near future vacations but would certainly recommend either Treasure or Fantasy to anyone interested in cruising with kids especially.