We just returned from a cruise aboard the Oasis of the Seas. When I asked my family of 10 if they found any negatives, the only things we could come up with were the walkie talkies didn't work because of the ship size and we would be let down with any other cruise ship after this experience.
From the moment we stepped aboard, we were wowed. We have been on three previous Royal Caribbean ships, one Princess and two Norwegian. This ship just seemed perfect. There were only a few times when the elevators seemed crowded. There were always deck chairs available for the sun worshippers.
The shows were all wonderful. We were hesitant to see Cats because of some of the reviews. In fact, I watched it twice. I took my grandchildren (ages 8-11) and they loved it. The trick is you have to sit in the front row. The singing and dancing is phenomenal. There is a lot of interaction with the audience if you are sitting in the front row plus you get to see the actors always performing even when not in the spotlight. It was an unforgettable experience.
Our cabin was good. I don't find much difference in cruise cabins but we had no complaints. Very quiet. Shower pressure always good. Balcony was a nice size. Some day I would love to take a cruise with a lounge chair on the balcony (maybe suites have this.) Our room attendant, Miguel, was always friendly. Actually I never experienced one negative employee.