We did Western with our 9 and 11 year old kids and it was amazing. We were on the Fantasy at the end of September and loved the different ports. We were told not to bother with Costa Maya but it ended up being one of our favorites! In Grand Cayman we did the reef/shipwreck snokel (about $35/pp - very reasonable!). The water was so clear! We brought a waterproof camera with us and got some great shots of the ship beneath the water and the kids snorkeling.
In Costa Maya we watched the dolphins showing off but didn't do the excursion. Then we headed to the pool at Senor Frogs, ordered margaritas and enjoyed the music while the kids swam. We were served lunch in the pool and even got to hold a baby lion while we were in port.
We had terrible weather in Cozumel and our excursion was cancelled (and refunded). We were still able to get off the ship in the afternoon for a bit and did some shopping and exploring in town. We did a non-Disney , the chocolate factory tour, which we did quite a bit of research on before booking. That involved getting a $10 cab (a rabbit with about 400,000 miles which stalled 3 times getting there - choose your cab wisely!) and then the tour was about $10/pp plus chocolate. It was definantly interesting and gave us a more realistic look at the city beyond the port.
And at
Castaway Cay we did the StingRay Excursion along with the rafts, bikes, snorkel equip package. The stingrays were the coolest thing EVER! Loved it! The snokel equip - not the best (compared to the equip used in Grand Cayman). The rafts were great and we enjoyed the bike ride around the island although my kids only did the slide once or twice - the lines were long and the water was a little deep. CC was still thier favorite port. The lunch there was rather disappointing compared to all the choices you get onboard. They ran out of plates, utensils and even food but they got it all together pretty quickly. Seating was crowded and I would pass on the lunch experience if I had to do it again but I'm not much for bbq and that was pretty much the only option offered.
Overall, we had a wonderful time. We were very happy with the Western, enjoyed our 2 days at sea on the ship, did Palo for lunch on our Costa Maya day (late arrival at port - 1pm), the Rainforest Spa (only used it twice - I suggest getting a day pass rather than a week's pass - hard to get your money's worth). Kids spent quite a bit of time in the Occeaneers Club and really enjoyed it but we still didn't have much time on our own, by our own choice. We prefered to do things as a family.
Happy Cruising!