We did the Black Pearl this year for a sunset sail. It was delightful. They served drinks and grilled cheese sandwiches as well as other snacks. You are on loungers. There are several snorkel stops. Some people went in and some did not. There were no children on board. It was a very calm relaxing excursion and we would absolutely do it again.
Boca Catalina, Arashi Beach Manchebo Beach, Eagle Beach
Another vote for Black Pearl. It is very relaxing. They do a wonderful job. We had no children on our tour either, but I'm sure that there are kids on there sometime. They have a limited number of passengers, so that is definitely a plus.