I just returned from AC on Sat. 1/20. I would strongly recommend Banyan Bay Villas. We had a ground level unit directly on the beach. All units are 2bdr/2ba, living room and fully equipped kitchen. The pool is the best I saw on the island - and I did check out the other resorts. There is a full service dive shop located on the dock right on the property that can arrange ANY tour/trip you want to go on - sailing, snorkeling, ruins tours, diving, etc. Eli runs the shop and she is very helpful and informative!
We didn't try to snorkel from the beach, I don't think there was much to see, so pay to go out on the boats which will take you to the best reefs anyway. Shark/Ray Alley is a blast and only $20 per person.
Maybe it was this past week, but we found things to be very quiet and relaxing. We practically had the pool to ourselves each time we went out for some sun. They were still rebuilding the bar and grill, but other than that everything was absolutely beautiful.
Have fun!
Lainie