We have just returned from a wonderful cruise to Japan, South Korea and Taiwan on the Diamond Princess. We totally disagree with all the complaining reviews of the ship. We loved it. The food was excellent, the cabin better than expected and the bed extremely comfortable. All the crew at every level were friendly, welcoming and very efficient and helpful. The ship was smart and clean and we enjoyed meeting the other passengers.
We have been on many many cruises and, while we prefer small ships, we found that size was not a problem on the Diamond Princess. Though it was busy, we rarely queued at all for food in Horizon and were always able to disembark as soon as we wanted to except at the one tender port.
The downsides: We don't like fixed dining as the times are not convenient.
Good storage space, better than on many cruise lines, very comfortable bed, good balcony, bathroom fine and again, better than some we have had.