In a nutshell, we had a great time and would go on this cruise again if the opportunity presented itself. It's not a perfect cruise, but considering the relatively low price, we were more than happy with what we got.
Here are some random thoughts and suggestions for those considering this cruise:
1) We intended to purchase "Faster to the Fun", but dragged our feet. When we went to purchase it, they were sold out. HOWEVER, we found getting on and off the boat at all points of the trip easy and well-organized. We didn't miss it.
We were disappointed in the size of the room and the layout. There was no tub (had one on Disney and Norwegian) and no curtain separating the kids' beds from our bed (again, had one on Disney and Norwegian). The balcony was small but we were glad we had one. One issue for us was there were few places to hang wet items. Consider bringing something to solve this problem. Also, there was only one outlet. I would recommend bringing an extension chord. I liked all the shelves in the bathroom. As mentioned in my general review, I recommend purchasing 12-packs of water through room service and then storing them in the refrigerator. It cost less than $4.
This was my favorite stop. You have to take a tender from the boat to the island. The process was well-organized and the trip to the island was less than 10 minutes. The water was unbelievably blue! White beaches, lots of lounge chairs to rest, big BBQ lunch (had vegetarian option though) made this a lovely day. We did not get a cabana because they sold out of them several months before the cruise. But they looked like the perfect place to enjoy the beach.
I would recommend staying on the boat.
Beaches and waters were beautiful, but the island itself was dumpy. We booked our own excursion with Blue Waters because we didn't like the snorkeling options offered by Carnival. I would give Blue Waters a 5/5 rating. We took a taxi from the terminal; it was about 7-8 minutes away. They took us to two different sites- one at 10 feet above a reef and the other 30 feet above a reef near the drop-off. Our guide was informative and very friendly. We saw lots of fish. We also were the only ones in the boat that day!