If Italy is the destination, and Tuscany is the focus .... Castello di Velona -- i second that vote, have stayed there myself, its very sweet. that neighbourhood in Tuscany is spectacular, and the wine (Brunello) is grand.
As for a spectacular place for dinner (beyond the hotel which is very good), a 7 km drive away, in very pretty Tuscan hills, is the Banfi estate. They also, by the way, have rooms now. Their dinner is over the top, also in a Castello, and they host a Jazz festival at the castel in July.
Google Banfi, send them an email, rooms aren't on LL. But Castello di Velona is now on offer. I suspect if you let the Banfi team know that "THE QUESTION" was going to be asked over dinner, they would somehow turn the event into something beyond spectacular.... a pretty walk between courses at the estate .... and the staff make the difference.
Italians are romantics beyond anyone's comprehension, and if they get to participate in such an occasion, they'll make it special.
Another gorgeous location in Italy is the Hotel Bellevue in Cogne, in Valle d'Aosta. Sometimes offered on LL (i have managed to secure it twice). The room was splendid, with a big (working) jacuzzi bath in the bedroom, fireplace in an ante-room, a lovely family owned hotel (Relais and Chateau) and a very cozy spa on site. It has an elegant and personal feel to it that makes it a place to which one must return.Former Kings of Italy have stayed there. Its in the middle of the Gran Paradiso national park, a half hour drive to the San Bernardo Pass to Switz, and an hour from Chamonix, France, and lots of little castles in the Valle D'Aosta area, so if they are looking for something like that, with three countries in the neighbourhood, this one is a gem. And the little village of Cogne offers a few low key distractions, nice walks, good restaurants, fresh air, calm and not hectic at all. Its neither Florence nor Venice though ....nothing can compete with those two.
From your description of the Valle d'Aosta, it sounds like the village of Cogne would be well-worth a visit the next time anyone plans a vacation trip to Italy. To be sure, Rome, Florence and Venice are "must see" destinations but I'm a sucker for castles of any kind (just loved the magnificent 500-year old Castillo de Morro at the mouth of the bay leading to Santiago de Cuba) and would make a point of heading north to Cogne just to see these architectural marvels, as well as the nature walks, good restaurants, and fresh air that you mention. What's the best way to get there from Venice? Rail, air or bus/car?
you have to have a car to see Valle D'Aosta. I suggest that you start from Milano, spend a few weeks if you have the time in the two regions, Valle D'Aosta and Piemonte. Piemonte is a wonderful region, offers three of Italy's finest red wines (Barolo, Nebbiolo, and Barbera), the town of Barolo is quaint, Alba is the home of Ferrero chocolates, and Martini (of Martini and Rossi), and there are wonderful Bed and Breakfast equivalent accommodations in the region. The food is excellent.
You could also spend time in Torino, recently spruced up from the Winter Olympics, one of the greatest collections of Egyptian antiquities outside of Cairo is in Torino, as well as a few pretty castles.
And if you are bored of all that, the Principality of Monaco is a day trip from Torino if you want to rush, or a wonderful few day visit.
Its a different view on Italy, is so close to Switzerland and France that it givesthat opportunity fora three country tour (plus Monaco, which everyone should visit once in their life) and has very pleasant views, excellent regional food and wine, and a slower and calmer pace than the top three... I find it relaxing, and I enjoy driving in the Alps, all seasons, so that makes it all the more attractive.
As it happens, driving is one of my favourite pastimes. And, the idea of driving (ideally in a rented luxury sportscar) in Monaco just makes my mouth water, because it's there that every year the best of all the Formula 1 Grand Prix car races is held on the streets of the tiny principality. I drool at the thought of driving on the same streets as Schumacher, Raikkonen, and Alonso have battled tooth and nail over so many times over the past five years! In addition, driving in the Alps has always been a dream of mine, so I really like your excellent recommendation for getting to the Valle D'Aosta. Your other ideas and suggestions are also very much appreciated and would be sure to make any vacation in Northern Italy a magical experience. Thanx!