My 10th cruise, my husband's 6th cruise, my oldest child's 4th cruise, and my youngest child's 1st cruise.
Our travel agent did not tell us there were any large groups booking this cruise. There were 1300 mostly teen-aged girls and their families with the Barbizon modeling agency competing in front of agents & scouts. They occupied most spaces with "private functions" as were we told by the signs posted at most public rooms. I felt regular activities/programming were light due to the group having their own agenda and using the spaces.
Service was pretty good most of the time. Exceptions were the breakfast and lunch open dining in the Mardi Gras dining room. The hostess often ignored requests to be seated at a table for 2 more people so that people we were traveling with could join us as soon as they arrived in the dining room (typically about 5 minutes later). One morning she moved us to another table after we ordered breakfast and our items did not arrive before the dining room closed.
Bar service was sometimes slow at the bar at the bottom of the atrium with only one bartender and a lot of guests. There are push-buttons for bar service in the Serenity deck area which indicated bar service within 3 minutes of pushing the button, but sometimes that went ignored. We sailed in two adjoining staterooms, R130 & R134 so that we could avoid bunk beds and have additional space. Our travel agent booked one adult in each room and one child in each room. Carnival changed it to two adults in one room and two small children in the second room. We kept the children's keys so that we could access both rooms from the outside. (This also created problems at dinner as we were assigned a different (adjacent) dining table than that of our children. We were able to switch with people to correct the issue.) The cabin steward did not set up the beds correctly when we first arrived. Cabin R130's bed was setup together against the adjoining door so that we could not open it to connect the cabins. To keep the beds together there was no good way to position the beds that would not block the adjoining door.
Food in the dining room was ok but not great. Lobster tail was not broiled and was served a little limp/soggy. The NY Deli on the Lido deck was great for fresh-made sandwiches. We were a little disappointed there were no made-to-order omelet stations or anything like that and there was no major late-night buffet. One night there was a mexican buffet out by the pool.
Both children participated in the children's programs. They were better than on past cruises. All children had to wear a wristband with muster station letter (regardless of program participation) and they actually had a plan for children in case of disaster. Another first for us. For our 3 year old, we had to carry a large phone with us throughout the cruise (whether she was in the children's room or not), but they never needed to call us. We did not want them to feed our children (and they push you to not leave your children during meals) but we wish they kept the playroom open during mealtime so that we could feed the kids earlier at the Lido ourselves and bring them to activities before we ate dinner. It would have given us, our wait staff, and our fellow diners more sanity! The 2-5 group stayed in the playroom and the 6-8 group varied location depending on the activity.
The casino was fun but there weren't a lot of variety of slot machines. The floor plan was very open. Not a lot of information was published ahead of time - most announcements were on the screens of the slot machines the day/evening they occurred - so we missed fun events like the slot tournament.
Disembarkation - fastest we have ever had on a cruise