I enjoy cruising and have taken several. We were on a charter Melissa Etheridge "Rock The Boat" music cruise. That part of the cruise was fabulous and we loved that part of it. We did enjoy the casual feel of the cruise and being able to wear shorts to dinner. There were no formal nights.
There were bands all over the ship at varying times. If you are interested in music cruises, I highly recommend that you google the internet for them. This was probably the most all out FUN that I have had on a cruise.
Downside of the Brillance: Had this been my first exposure to cruising, it is doubtful that I would ever cruise again. The food, for a lack of a better discription: SUCKED. Tasteless, overdone, inferior quality, you name it, it was all there. Outside of the couple of soups that really were excellent, the food at the Windjammer was mediocre at best.