I am going to Italy in September 2017 with my wife and need help with respect to planning.

I have Florence taken care of (in terms of days etc...) but for the rest of Tuscany I have 5 days and 4 nights dedicated to which I would like to do the following:

San Gimignano and Volterra
Pitigliani, Sovana and Sorano + Maremma
Gargagnana
Siena perhaps if I can fit it in (or other suggestion or two)?

Could someone advise where would be the best base to stay (can be multiple locations for sleep).

It would be really cool to stay in a castle or two presuming that the rooms provide full services. And of course I would like to go to some vineyards, sip wine and have great meals and interest in visiting medieval towns which hopefully I have covered but am open for suggestions!

Also can someone suggest itinerary together with drive times to each locale?

The other places that I will visit during my visit is Rome, Milan and Turin so after wrapping up in Tuscany should I head to Rome to finish or head to Milan (or Turin). Thank you!

Thank you