Enjoyed this one completely, and the weather was great as well!
All of the excursions I booked through the Royal Caribbean desk, the first day of cruising. You can go online and make sure you get the code and what you want. The prices are the same online versus at the desk.
I recommend snorkeling in both Bonaire (3.0 hours) and Aruba (5.0 hours - 2 snorkeling sites, lunch and time on a nice beach, I even got vegetarian food which was delish!), and El Yunque rain forest on San Juan the day of departure ((5 hours - also an opportunity for food, but you do have to purchase, it is not included in the price of the trip) if your flight leaves later than expected), they also hold your luggage at the airport when you arrive, with someone watching over. It was coordinated nicely! I also did two spa treatments on the two days of cruising, and did the deal of the day - $79 for 6 treatments and $119 for 8 treatments. Also for the ladies, go to the pampering class on the first day, you get a lot of freebies including an add on to a future spa treatment! The food was awesome for a vegetarian as well, the chefs at the main dining room seating at dinner were accommodating to all allergies. The windjammer cafe for breakfast and lunch was also equally delicious. I had the opportunity to try the green, fresh smoothie at the solarium in the morning after my shipshape workout and walk around the deck when we were coming into port every day. Awesome! Prepared right in front of you.
On St Maarten, I opted out of taking an excursion and paid $7 for a water taxi, and $10 for an umbrella + 2 chairs on the beach. The water and beaches available on either side of the pier are perfect, and no need to look any further for better beaches!
In Curacao as well, there weren't as many excursions to choose from. This was by far one of the best ports to do shopping, since the stores were more in comparison to the other islands. If you are interested in exotic fruits to try, at the end of the floating pier on the left hand side, there is a market, very reasonably priced and they take USD as well. Just be aware of the conversions ahead of time.
One item -- they don't let you fill up waterbottles on board. Your best bet is to buy waterbottles from a grocery store every day on port. The Evian water they sell onboard is ridiculously priced at $9 per 1.5 liters.
Pre-paid gratuities and their $13.50 per day works out exactly the same. Be sure to check your onboard spending account prior to disembarking to check for any anomalies.
I did have the opportunity to buy voom internet service for one device on board. It worked out very well for days in port and at sea. The service is slower than what we are used to, but for important wifi calls or emails, it was very useful! I recommend purchasing this ahead of time, as on the ship it goes for $13 and $17 per day.
Overall I would do this cruise again and more from Celebrity and Royal Caribbean!