I recently got back from an Easter cruise on the Ecstasy. There were four of us (late 20's early 30's) who went together. I booked the cruise as a b-day present for my boyfriend who had never been on a cruise before and my brother and his girlfriend decided to come along too.
The weather was horrible in Galveston the first day (freezing cold and rainy), but getting on the ship was really easy and painless. We did the FunPass thing, but the other embarkation line was about the same length. When we got on, our rooms weren't ready yet so we sat in the Atrium bar and had a drink and watched people get on. Quite a diverse group of people too:) When our rooms were ready we checked 'em out and I was very pleased w/ how clean they were. Our room steward Eldar (sp?) was awesome and very creative w/ his towel animals. Dinner in the Wind Star was great and so was our waiter Rodonte! I liked that dining room better because it didn't move as much as the Wind Song.
On our first day at sea things got warmer really quickly and we were hanging out by the pool in no time. The kids on the cruise loved the water slide, which was open on both sea days. A sidebar on the kids- I guess there were 700-800 aboard and I never even noticed! The Camp Carnival people keep them busy all the time.
Cozumel was great! The water was very pretty. Since we didn't have a shore excursion planned, we waited until the majority of the people got off the boat before we attempted to. I would suggest this if you don't like standing in log stuffy hallways w/ 1000+ people. Paradise beach was fun and the food was great, but if you like quiet beaches I would suggest somewhere else.
Progresso was my favorite stop. The cruise ship parks way out on the pier and you take a bus to the town (if you want to go). There are shops and stuff right there too. Stuff is cheaper than in Cozumel! We took the Chichen Itza tour. Our guide Saul was great and knew a lot about the subject. The ruins were awesome and I would highly recommend this tour if you have never seen them and have an interest in this sort of thing. The only problem? It's a 2 hour bus ride each way, but you get to see some of Mexico.
We checked out pretty much every bar on the boat. Our favorite by far was Chinatown because they had an awesome band every night. The Coming Attractions (or something like that) played classic rock and stuff and watching everyone dance was quite amusing. The Society Bar was also very nice.
If you are in any sort of hurry to get off the boat at the end- SELF EMBARK!!!!!! We weren't, but after waiting for our color to be called and then getting off and getting our luggage and standing in an immigration line for an hour (not exaggerating) it was 11:30 by the time we got done. The only way to expedite the process of immigration was to vomit on the floor, as the kid in front of me did. He and his family were pushed right to the front of the line:)
In short (after the long)- we had fun and I think pretty much anyone would have fun on this boat. You just need the right attitude. Hope this helps someone. All the reviews I read before I went helped me a lot.