Wow...liking the American vibe isn't something you hear often from Europeans 😀
I'll return the compliment by saying I love your food and beer
Anyway, you got good answers but I will say in terms of stuff to do, the newer ships from carnival, royal, etc have more. For example, on royal ships you can do simulated sky diving, bumper cars, ice skating, rock climbing. Royal and Celebrity have escape rooms (the latter done in a non traditional way, but still...)
This isn't a knock against MSC, just saying those are differences.