We just returned from Italy, and our itinerary was close to what you are thinking of. We started with 2 nights in Rome, then 3 in Sorrento, 5 on the Amalfi coast (a home between Atrani and Minori), 7 in Tuscany (Val D'Orcia) and 2 more in Rome. We had no rental car until we left the Amalfi Coast. We rented the car in Salerno and drove it up to Tuscany, kept it until we arrived back in Rome. The one way fee to rent in Salerno and return in Rome was very modest.
In Tuscany, we stayed at Agriturismo Cretaiole, a five minute drive from Pienza, in the Val D'Orcia region. It is a centuries old property, beautifully renovated into seven lovely apartments with kitchens, and a common veranda room. The property is beautiful: a vineyard, an olive tree grove, cypress trees, a location high on a hill with a wonderful view of the Tuscan countryside. It was our second stay there. Our first was in June of 2017. Five of the apartments are for two people, while one holds 4 and one holds 6, so it can have up to 20 guests. Both times we were there, a honeymooning couple was among the other guests!
Cretaiole guests can sign up for the optional "Dolce Vita" package that provides a large welcome basket of food (enough to prepare breakfast every day and an appetizer platter every afternoon), along with the opportunity to socialize with other guests in a variety of activities throughout the week. (They also offer an ala carte opportunity to just pay for whichever of those activities you desire.) The huge guest book in each apartment, and the concierge at the property, provide tons of information on places to go, things to do, how to get there, when it's best to go, where to park, etc. And the concierge will make reservations for you. You will spend time with the family who own the property if you sign up for the Dolce Vita package . . . 81 year old Luciano, his son Carlo, possibly also his 22 year old grandson Niccolo--a recent graduate of a hospitality school in Switzerland--unless he has taken another job by May. Luciano's daughter in law, Isabella, wife of Carlo, was very present when we were there in 2017 but these days she spends all her time at the other property that she recently opened, La Moscadella in Castlemuzio. (La Moscadella is gorgeous, with a swimming pool and a beautiful dining room where you can have chef-prepared meals. We looked at staying there, but we wanted the more rustic property and our own kitchen.)
On the trip we just got back from, we did easy day trips to Pienza, Montalcino, Montepulciano, Cortona, San Quirico, all towns with a lot of shops and restaurants, and also wandered through some smaller towns in the area that were lovely to see but didn't offer much in the way of shops and restaurants at the off-season time we were there (first week of November). Those included Bagno Vignoni, Montechiello, Sant Angelo in Colle, Castlemuzio, Sant Antimo. One day we left Tuscany and spent the day in Orvieto in nearby Umbria. It was only a 1.25 hour drive. On our prior trip, we spent a day in Siena, and I remember that the honeymooning couple spent a day in Florence. The concierge does offer to set you up with a driver who will take you to Florence for the day, if you don't want to make the drive or take the train. A fun thing in June of 2017 was the afternoon we spent enjoying the hot springs at Bagno San Filippo.
Siena and Florence and Orvieto would give you plenty of night life but if you were staying at Cretaiole, you wouldn't want to be that far away that late at night. I don't know how lively any of the closer towns are after 9 or 10. We never stayed out that late on either of our trips. We were there with friends both times and did most of our socializing back at the property. In general, people in Europe dine late so I have to believe that the restaurants that serve dinner are open late, taking reservations past 9 p.m. Whether there's anything to do after you are done dining is unknown to me.
