What a great cruise! We just returned on Jan. 26th and loved our honeymoon cruise. Drinks are expensive. Pack what you can to save moola.
Scuba diving in Roatan was great!
Belize--Cave tubing and zip lining--long bus ride for a short trip....all excursions seemed to be overpriced. Recommend bartering with the locals when you get off the ship.
Cozumel...snorkeled with the locals but you could just as easily go to the national park or wander down the strip to snorkel off shore--you'll see lots of snorkelers so you'll know where to go....it'll save you and isn't too far from the boat.
We went to Nassau instead of the island so no recommendations there.
Hanging out in the hot tub is a great place to meet people and also hear about others shore excursions. We stayed on the Viking deck--though I'm a Packer fan by far--and thought it was great. If you want, I recommend calling to see if you can negotiate an upgrade to a room with a balcony if they aren't full.
Oh and for disembarkation, if you carry off your luggage, you can go at anytime.
Have fun! We're already planning our next cruise!