We have sailed on MSC 5 times - sometimes in YC, sometimes not. The last one was in Europe and not in YC. @Essiesmom is spot on. Sometimes people go into the cruise with different expectations than reality. Even the US based cruises are way more diverse in passengers than American cruise lines. We have had hiccups on occasion, but overall have been very pleased with our experience with MSC. Announcements have always been made in English and a few more languages.
We are similar to your ages (child is a little younger). Our next trip is in YC, and I would absolutely recommend it.