I would only differ in the TV others have posted.
On the Regal Princess, in a suite, the On Demand selection was absolutely incredible!!
On the Equinox, in a suite, the On Demand was absymal. I was actually shocked at the very few choices. (Fortunately, I had brought my fire stick and hence it was not an issue.)
I certainly agree with Honolulu Blue about the buffet layout on the Ruby...rather stuffy and lord help you if it's really busy!! I completely rearranged by dining schedule because of that...