First let me state that the quality of the entertainment in the theater was the best we have ever experienced on a cruise. My wife even gave a standing ovation to the final ensemble show.
The ship is beautiful but public bathrooms are not plentiful or convenient (ie the rear of the cafeteria area where you must go up a level to find the nearest one.
Unfortunately, MSC is in the Carnival class. Too many kids, wildly roaming the ship , especially late at night with no adult supervision. As the week wore on and the 'packs' materialized, we found elevators commandeered with teens sitting on every inch of the floor. Not threatening but detracting from the enjoyment you pay for.
The crew seemed nice enough but poorly trained. The wait staff in the 'cafeteria' stood or walked in the aisles without regard for the traffic. Service was erratic some good but a lot more chatting than on other cruise lines (ie Holland America).
Then there was the obvious emphasis of the captain on multi-lingual announcements. There is no problem to do this for life boat drills, disembarkation, etc. where info is needed. However, it is taken to an extreme, especially by the cruise director who seems bent on demonstrating her lingual skills. The topper was the Bingo where the balls were called in several languages even though the 'B15' showed on a screen in three foot characters.
Communication was poor. The daily planner is the worst I have ever seen. It contained repetitive advertising and hours of operation but didn't provide comprehensive information on the activities of the day.
Another communication problem was with the Internet. A wireless package was sold online but could not be used with the Cyber Cafe terminals. The service was so slow (passengers using bandwidth for Skype, etc.?) that if you logged on at the Cyber Cafe with your room card you may not get any meaningful service but you will be charged $5 minimum (for nothing!).
The food was good but the main dining areas, including the cafeteria, were jammed together, had hard surface which amplified the noise of families and foreign languages competing with each other to be heard or ???