Story - In summary, girl falls in love with man older than her stepfather. But this isn't one of your shoujo-type productions. This one actually feels kind of adult. I mean, normally if an anime cast features one main female character and an entire ensemble of guys you'd expect a reverse harem or something, but that doesn't happen here. They don't even have gags. Instead the humour is a sort of light-heartedness and happiness present in the dialogue. That is to say, rather than doing funny things to make the audience laugh, the characters instead infect the audience with their own joy.
Now, it's my opinion that the introduction you read on the main page is horribly misleading. The anime doesn't really tell the story of a courtship at all, except for maybe in the first and last two episodes or so. Every other episode is essentially an investigation into one or two of the cast members, and an exercise in character development. Each character's history becomes a story in itself. The tale seems to be more of one where you get to know the cast rather than one where things actually happen, hence leading to its slow-paced style.
Episodic productions tend to have more room for character development in their cast, since it doesn't have to share so much airtime with an overarching plot line. And Ristorante Paradiso exploits that advantage the fullest. You'll be amazed at how well the cast has been fleshed out and brought to life. You'll be even more amazed at how normalcy has been made entertaining, and how little personal quirks have been woven in.
Sure there's some use of stock tropes here and there (methinks it impossible to name a single modern series that doesn't feature at least one tsundere somewhere), but it's done tastefully and elegantly. It's precisely the sort of understated grace and class one might expect from a streetside cafe restaurant in Rome (although I've never been there, just employing the popular perception here).
Animation - Well it's not anything that will blow you away, and easily the weakest link in the production. The colours are ordinary, the contours unremarkable and the character designs not pushing any boundaries. On the other hand, there's nothing to fault the artists about either. It's, shall we say, perfectly adequate, with no outstanding qualities and no damning ones. You might find the faces a bit strange to look at in the beginning, with the high nose bridges and all, but I suppose they were just trying to give everyone a Mediterranean look. Can't judge how well they did there, but I think I can say that the studio wasn't very concerned about making the cast look good. If anything, they look decidedly plain, even uninspired. Nevertheless, it's a satisfactory piece of work without any crappy art or effects that might distract the audience. Except the OP. That one's fantastic. Look out for Luciano's steely stare as he stands by the side of a street in Rome decked in a coat.
Sound - Both the OP and ED, while not the best out there, fit well into the production and leave a rather strong impression. The tracks played throughout the series may not be particularly commendable, but I enjoy how well they were managed. They did what background music is supposed to do: stay in the background and cast the mood without interfering with anything else. At times, I didn't even realise music was playing until the scene changed and the track faded away.
The voice acting is superb, especially when you consider that they're a bunch of relative unknowns. Ristorante Paradiso's seiyus seems to effortlessly portray each character’s personality through their voices, and do it so endearingly one cannot help like them. I also enjoyed how bits of Italian were mixed into the Japanese lines. Seamlessly done, if not for the subtitles I would have real difficulty distinguishing the two.
Characters - Ah yes. Easily the strongest element of the series. I can confidently say that out of its ensemble cast, there is definitely at least one whom the watcher will take a liking to. Perhaps it is Nicoletta's maturing, Claudio's gentle demeanour, Luciano's gruffness or Gigi's quiet cool. But definitely at least one will grab your fancy.
I'll take it further and say not a single member of the entire cast is dislikeable. Yes of course I know it's subjective, but it is my frank opinion that unless you are heavily prejudiced towards a specific character trope you will not find anyone to hate in Ristorante Paradiso.
I will, if I may, compare this to Working!!, in that both successfully character tropes into their roles excellently without necessarily breaking new ground. But while Working!! took the funny-bone path, Ristorante Paradiso picked an entirely different, more sophisticated direction. And without the random gags stuffed one after another.
Like I mentioned earlier, Ristorante Paradiso is almost pure character development, and as one might expect the cast is given a healthy level of depth. It was a splendid decision by the studio to devote at least one episode to each member of the ensemble cast's backstory; characterisation truly takes centrestage in Ristorante Paradiso and it is an excellent lesson in such.
No cast member is left unexplored or undeveloped, and no question is raised and left hanging. One is left with the feeling that even though there's no way the series could had covered their entire life stories, one knows for certain that the key points were addressed fully. That makes the series so much more engaging and leaves it with a wholesome sense of completion.
A commendable effort I noticed was an attempt to vary how each character's tale is told. Now with a flashback, now with someone else relating his story, now with Nicoletta making deductions based on what she already knows, now through his actions and choices when faced with a dilemma. I completely understand those who find episodic slice-of-life productions tiresome, because more often than not every story ends up doggedly tracking the same pattern. Not so in this Ristorante Paradiso.