I believe I read in the last week on this board that the Banana Boat rides had been cancelled, at least until
DCL can find a new operator. My DS13 went on it in November and had a great time.
Regarding Serenity Bay, I think it really depends on the time of year and the weather. In mid-November, we had a day that was windy and cool. The waves were really choppy, and most of the water activities were cancelled. They did resume Banana Boat rides later in the day, but even sailing was only for very experienced sailors. Serenity Bay, that morning, was cold and the water way too rough to go in. On a nicer, less windy day, it would be great! That morning, not too many people were going in the water at the Family Beach either. I guess I would recommend you try it out and see. Later the same day, the wind died down, the sun came out and it was much nicer all around.
As you guessed, hammocks go very quickly. The one place that there always seems to be a couple available is at the far end of the beach, toward the Bar that's near the Sports and Teen Beaches (can't recall the name).
I personally think the Flying Dutchman makes a nicer photo from a distance, with or without the Magic in the background, but didn't do the wave runners, so I can't really address that. Only one side of it, though, is "finished"; the other is clearly a movie prop.
Hope some of that is helpful.
CC was the best day of our vacation. DH and I dropped the kids off at Scuttle's Cove and Flounder's as soon as we could. Then, we were off to Serenity Bay. We relaxed on the beach, sitting in our chairs with our feet in the water drinking some yummy Midori Coladas (our new favorite drink). It was a perfect vacation moment. There are servers that come out onto the beach to take your order. We even had the server take our picture for us. After relaxing on the beach, it was time for us to head to a cabana for a couples massage. It was soooooooooo relaxing. The time went by way too fast. After that, we had a nice childless lunch. I had grilled chicken and DH had a burger. Then we hesitantly, headed back to the family area of the island. DH and DS6 went snorkeling after lunch. I had read other threads about going snorkeling in the morning to get a clearer view. DH said it was just fine. They had the best time. DS6 was so excited he found the hidden Mickey and saw a lot of fish. DH was scheduled to parasail in the afternoon, but it was canceled due to high winds. He wants to do that next time. I had a hard time getting DD4 out of Scuttle's Cove. She was having fun playing and getting the CMs wet. We were so exhausted when we got onboard. The kids were falling asleep at the pirate party that night! It was a fun-packed day we won't soon forget! 
We spent most of our time
Nice lunch and perfect weather that
