We had a great experience on this cruise, even though the ship was older and 90% or more of the passengers spoke Spanish! The ports were all excellent, and the service was top notch throughout the week. We made some good English speaking friends (many seemed to be clustered in the aft junior suites) and also enjoyed the company of our Costa Rican dinner-mates (who fortunately also spoke English and humored us as we attempted our grammatically-challenged Spanish).
The ship, though showing its age in many places, was still overall very clean. We enjoyed the larger wind-free balcony this aft junior suite provided, especially as we overlooked Curacao and the floating bridge. The size of the ship overall was cozy but never really felt overwhelmingly busy.
The Windjammer (we only eat there when it's the only thing open, which was lunch on port days) always seemed like a zoo, even at 3pm. There's something about buffets that can turn people into savages, and here it was no different. We were told it was crazy at breakfast (others on the ship mentioned shoving and line cutting and no place to sit). Breakfast every morning in the main dining room was relaxing however and definitely underused; it was half buffet, half menu, so we typically got fruits on our own and smoked salmon/pancakes from the servers. The main dining room was also open for lunch on sea days, and we always opt for the make-your-own salads. Dinner times were 7pm and 9:30pm (an hour later than the times we'd seen on other RCCL cruises), but most people show up late (15-30 minutes) anyway. Our server mentioned that it was routine for people in the second seating to show up close to 11pm and expect to be served.
The entertainment was almost all in Spanish, but there were also the standard tacky production shows which are sung in English. There was a comedian the first night, but he spoke too fast so I only got half of the jokes. The fluent crowd seemed to really enjoy him, however. There was a Beatles tribute and a plate spinning acrobat, and these were both good. We really enjoyed the music in the Centrum and by the pool (especially Zafiro, the trio from Panama that are apparently part of a larger group) even though they played only Latin music. It was nice to have a chance to listen to something different.
Overall, we really enjoyed our trip, and the immersion part played a big part in how fun the trip was for us (the ports were also all very good). Remember that all the crew will be able to converse with you in English, even if the fellow passengers cannot, so I'd encourage anybody considering this cruise to do it! I think it will only get better next season after the planned renovations in April!