We have been on 10+ cruises with Royal Caribbean. We're experienced salty and seasoned cruisers. In the last year we've been on the largest ship RCL has the Wonder of the Seas to the smallest ship Grandeur of the Seas. The Brilliance of the Seas falls right in the middle of the the two ships mentioned above. We really liked the ship!
The ship is a little dated but it has good bones. It didn't have all the bells and whistles of some of the newer ships (water slides, Flow Rider and so on), but we felt it offered a good value for our cruise dollar. The offerings on the ship kept the good common standard service, entertainment, great crew and food that you will find on all Royal Caribbean ships. Everyone seemed to be having a good time!
Our balcony cabin was clean and very comfortable. Having the room serviced once per day was enough for us. We chose morning room service.