Although our kids of 10 and 7 were meant to be in different groups, when I took them to the kids' club, there was one able-bodied girl looking after the group of about 25 children, with the assistance of another with a broken arm.
The average age of the children was probably about 5 or 6, so both of our kids refused to stay in the club, and I could understand why given the babyish games they were playing. Ours were not alone as I saw other parents accompanying their children to the club, and the kids also refusing to stay. Not what I expected at all, and is something MSC must address.
Other than that, we were lucky that because we had taken an Aurea suite as there were 4 of us, we had priority when it came to boarding and unboarding, which worked well.