I could not agree more. When we first cruised in 2004 with our sons, 15 and 11 at the time, it was perfect. There were planned activities for the kids that they enjoyed. We could give them a bit of freedom while we were able to relax by the pool or enjoy an adult comedy show. We all got together for dinner and excursions. The excursions gave us all an opportunity to do new things (cave tubing, for example). We ALL had a blast! And it cost no more than a week in Orlando (and us old folks were less exhausted!).
We have cruised 2 more times since, the most recent with just one son, age 19. It was a different experience. No more kids programs, but he checked out the casino and enjoyed some of the shows, etc. Still lots of Bang! for our $. We probably got to enjoy his company more than if we had done a traditional vacation because he probably would not have come!! But who can turn down a cruise???