Being on the ship on a holiday isn't like being at WDW on a holiday. The ship can only hold a certain number of people....they can't pack them in like they do in the parks. The passenger/space ratios that you can find in the promotional literature are based on full capacity, so you would actually never be crushed by the crowds. WDW can very in attendance from something like 15,000 vistitors in a day to maybe 125,000 in a day.(??) The ship isn't like that. It is full a lot of the time. There will be more children, but there are always a lot and the activities are always plentiful and "up and running." You will pay a lot more for that week vs. the week before or after though.