Well, first I'll say that I never (& I mean ever) wanted to go on a cruise and now we've booked another one so that says a lot! So for now, since I'm not sure what you all want to know I will tell you a little about our excursions and what I found very useful and what I didn't. It was my husband, myself and our daughter who turned 13 on the cruise. She will turn 14 on this one. This give you perspective on where we are coming from.
Grand Cayman - Extreme Dolphin Encounter and Turtle Farm I highly recommend this. They were both great. Loved interacting with the dolphins and being able to pick up baby turtles. A little piece of advice that we read and used: You may not take photos at the dolphin encounter because they want you to buy their photos. The prices are negotiable. Most people in our group bought a few photo prints and got a dolphin USB device with the same photos for a couple of hundred dollars (US). We got all of our photos on a disc (70+) with no prints and no cute USB for $99 - a much better deal if you ask me.
Our next stop was Costa Maya but we won't be going there so I'll skip that.
Cozumel - Mr. Sanchos booked through their website. It was fun and relaxing. We will definitely go back. You need to get a cab and go over. It was $17 for the cab ride. We did the all inclusive which I recommend. The food and drinks were well worth that price. It also included lockers and snorkeling equipment. As well as probably a lot more that we didn't try. Everyone was friendly there. Got massages that were $50 for 45 minutes. That was great and much cheaper than the spa. The only drawback and it was very slight is that the vendors at the entrance were sort of pushy but it wasn't a problem.
Castaway Cay - Here's my advice. Don't forget to take off your lanyard before going in the ocean.
Our daughter lost her key to the world in the ocean. Not a huge problem since it was Disney's private island. We did the "extreme" package here but I would not recommend that. We did the stingray encounter which was very interesting and fun. You got to even snorkel with them. I don't advise general snorkeling at CC because there isn't much to see. We did it because it was part of our package but not really worth it. The aqua trikes look a lot more fun than they actually are. Loved the rafts and tubes but you can get those at the site. No need to pre-book those. CC is gorgeous and fun. Pack plenty of sunscreen. You will need it. There are lots of places for shade here but let's face it, you'll want to play in the ocean.
We did magnets for our door, which was very fun and also made finding our room easy.
We ordered a birthday cake which I would not do again because over 1/2 of it was left. There are just so many yummy options that you can't eat everything.
We did not do the FE nor will we. I love that people love it but we couldn't even try to do all we wanted to so the idea of walking around the ship finding all the FEs didn't appeal to us and since we fly in it would also be a hassle to pack them all. For the people that love that - awesome!
Since our daughter is older and didn't want to stand in line with an autograph book we dropped off a frame matte and a pillow case at guest services for autographs along with Sharpies. All were delivered to our stateroom on the last evening. That was really neat.
We loved getting dressed to the nines for formal and semi formal nights.
Things we brought that were helpful:
Lanyards are the BEST for your Key to the World card (aka stateroom key)
Travel drink cups – the cups on deck are small. If you bring travel mugs you can either carry around coffee or soft drinks
clothes pins - there are two lines in the bathtub to dry wet bathing suites but they all slide to the center without the pins. Some people also use them to keep the drapes closed if you want to sleep in. We didn't find that necessary.
Magnetic clips - could clip the Navigator and the excursion tickets to the door so you weren't trying to find them nor did they take up space.
Hanging shoe bag - they no longer allow shoe bags for over the door because they damage the door but you can take one that hangs in the closet. That worked out very well for all of our shoes and belts.
Pair of small scissors – came in more handy than I’d have thought
Suction cup hooks – great for hanging lanyards on so they don’t get misplaced
Collapsible hamper – We kept ours next to the sink in the shower/tub area for dirty clothes.
Ziplock bags (quart & gallon) – excellent for a multitude of things ranging from keeping things somewhat dry (not waterproof) at the pool or bringing a snack back to the room.
Some sort of bag to take on shore excursions.
Things you don’t need:
Multiple purses to match your outfits. The only time I used a purse on the entire trip was on formal and semi-formal night because I didn’t want to wear a lanyard but if you or your spouse have pockets you could even do without a purse on any night.
Shampoo, conditioner or body lotion – these are all provided for you and are great products.
That's all I can think of at the moment but would be happy to answer any questions since we just got home from a 7-night on the Fantasy and it is fresh in my mind.
How was the weather? We went to WDW last year the same week and it was back and forth. Rain, sun, clouds, hot and cool. FL weather changes during that week'ish, but what about at sea? Took a risk for storms for the price decrease. Totally worth the risk. 
