Paradise Villas is a good place for families and you can snorkel off the dock at Wet Willy's right in front. There a lots of fish as they are feed scraps all the time. The local kids like to play in the water at the next dock over. I have seen some of the most incredible stuff snorkeling in this area.
Capt. Ron also has a two unit condo at Paradise Villas that he rents out separately. This is an up and down beach front unit and could probably handle your group of six as they have sleeper sofas.