I too have had a poor experience on the Ryndam.
The Lido was horrible - reminded me of a chimpanzees tea party.
I have now read several poor reviews of the Ryndam. Note 2 years ago she was on the Alaskan run and now the vessel has been dumped on Europe. The vessel's cruises in Europe are not selling well - I wonder why?
Overall the experience was poor - when I posted some very short comments - someone said try HAL again? I say again if you go to a restaurant and have a lousy meal - would you go back?