We just got back from the Western Carribbean. We absolutly LOVED the stingray and city tour. I have a 3 year old dd who was too young to do it through
DCL, so we contacted NativeWay and they did the tour for us. It was fantastic. I would highly recommend them. All the kids (14 ds, 11 dd, 6 dd and 3 dd) loved the stingrays. It also goes to the Turtle Farm, which was amazing.
We did the Mayan ruins in Costa Maya, which was really neat. However, it was HOT. Be prepared for that. We did it through DCL, which was good because we made it back to port at the time the ship was supposed to leave. We would have been freaking out if we weren't with a DCL tour.
In Cozumel we did the Dolphin Encounter (you can also do the Dolphin Swim). The encounter takes about 30-45 minutes. After the time with the dolphins you can stay at the park where they have a fun place to snorkle and a fresh water pool to swim in. We loved this one as well.