Well-trained and consistently-trained staff. Unfailingly (apparently) happy in their work and with good people skills.
Good sense of humour (necessary to rebuff the complaints about the food).
Relentless up selling of drink options. (I don't WANT your "special" marguerita - I want an ordinary one!)
Poor organisation in breakfast buffet, though with all waiting staff either assigned to drinks duty ("More coffee, sir" , every three minutes, even when cups still full) or to cleanup when the under-managers were on the prowl (three separate mornings when NOBODY came by our table to ask if I wanted juice or any other drink, I was reduced to pouring it for myself, which of course led to protests from the staff member who noticed!). Wouldn't it make more sense to have some staff assigned to each duty type at all times?
Food in main dining room (8.15 sitting) bland and uninspiring. I was tempted to attend the culinary demonstration in order to find out how they managed to remove any flavour from what were (presumably) reasonable-quality ingredients.
The highlight was the fried sushi rolls, which were inventive and imaginatively-presented.
The lowlight was the food on the Italian night (for some reason scheduled on Halloween, some five days after we had left Italian waters), where great skill had been applied to the desiccation of both fish and meat main courses.
The evening entertainment in the theatre varied from reasonable (Siobhan Phillips - beautiful and unusual voice), through adequate (Freddie Mercury tribute), to pathetic (the "other" David Copperfield). Some people seemed to enjpy Copperfield, to judge by the laughter (unless he had a backing tape set up), BUT I have to say to my US co-travellers that this was not "wacky British Humour" - he simply was not funny!
The nightclub appeared to be patronised largely by off-duty members of the entertainments team, but was a lively place to relax with a post-prandial marguerita. Adagio was altogether more refined. We just didn't like the lack of atmosphere in wheelhouse, explorers, or crooners, but plenty of other people did.
Daytime entertainment appeared to be focused on separating guests from their money (Casino, Art etc). Except, to be fair, the various musicians who played in the Piazza. Special mention should be made of the Atomic party band, who were able to turn their hands to many different styles, but were at their best when allowed to rock!
Room was comfortable (inside, Riviera deck), very quiet and supplied with all necessities. I found it strange, though, that a US-dominated boat appeared to have no shoe-shine facilities, nor did our steward seem to understand what should be done to clean and shine a pair of brown leather shoes.
Only ended up taking one tour. The staff member assigning us to buses failed to notice the important words "guiados en Espanol" on our tickets, leaving the guide at Olympia to make some hurried phone calls to get us out of the English-language group from bus 11 and onto the Spanish group from bus 14. The other tour we booked was cancelled, so we instead did Ephesus on our own, as for most of the other ports.
The guests were split 1500 US, 500 UK, 500 Aussie and 500 "other". Ages ranged from one year to about ninety, the median being around fifty. The US folk seemed to stick together, but the non-US mixed well (and I include the Latino Yanks in "non-US" here - it was the Anglo-Yanks who seemed to be the most stand-offish).
The itinerary was great (Greek Isles, Venice to Rome), but I don't think we will be back on the Ruby in a hurry.