I just went to the western Caribbean on the Elation in August. Here is my review:
http://www.cruisereviews.com/Carniva.../Elation79.htm
Why don't you take a look and then ask any more questions you might have??? Obviously the hurricane has caused a lot of damage- particularly to Chankanaab Park, which I mention in the review. I think everything else I experienced is still pretty much the same. I don't know what your itinerary is, either...
I don't know about the soda cards. My kids just drank the lemonade and iced tea. Tipping is covered all over this site, but mandatory gratuities are 10 bucks a day per person. I believe in tipping above and beyond that, and if you want to chat about amounts, let me know.
Good luck.