Where to stay near Siena…prefer B&B or agriturismos

We are 4 woman friends traveling to Italy for our first time. We are planning to spend 2nights in Rome with private tour, then train to Positano for 3 nights.We plan to spend the middle of our trip 4 or 5 nights in Tuscany, near Siena. We had booked this trip last year, but had to cancel due to family emergency. We had booked Frances’ Lodge, which we fell in love with, but she doesn’t have our specific dates available this year. Do you have any other suggestions? We want to stay with other guests and have breakfast/dining options. Probably more questions coming once we settle our lodging. Thanks Elena!