We did 8 night Bahamas cruise on Anthem this past March break. We are from Ontario, and almost everyone was from Ontario on March Break. There were over 1000 kids on the ship. We missed out on CocoCay (pier wasn't built yet and the waves were too big), so we only had two port days on an 8 night cruise and we weren't bored. My kids were 4 and 6. For bumper cars, trapeze, etc., we would get in line about a half hour before the event started, and would usually be in the first or second group. Note that a kid has to be 5 to do the bumper cars (my 4 year old was 2.5 weeks shy of 5 and was not allowed), but kids under 5 can roller skate if their feet fit the smallest skates and an adult goes out with them in regular, closed toe shoes. I did ask one person in the bumper car lineup in the middle of the time slot, and they had spent an hour in line. We never tried to get a ping pong table, but those looked busy. Only 2-3 of the 5 XBoxes were working, but my girls did get a chance to play
Lego Marvel Super Heroes (they love the Lego games on the XBox) without a super long wait. All the indoor spaces were great when the weather was cold (March Break this year was pretty chilly). The family events, like family bingo, were crowded. They ran out of bingo cards and had to turn families away. When the weather was good, the rock climbing lines were very long. Flowrider lineups were OK when my husband tried it. My kids only went to Adventure Ocean a few times, and they got in, but I did hear that some of the AO rooms sometimes filled. There weren't any Dreamworks shows, but there was a dance with a character-type events, as well as meet and greets.