Driving from Assisi to Florence

I would suggest that one stop you must see is the place to turn in your car before you enter Florence. All of the historic area is in a restricted area. They get your license with cameras. Large tickets for intruding into these zones. Google Florence ZTLs. That being said, there are a dozen or so very nice towns and cities to drive through on your way to Florence. Perugia, Cortona, Arezzo, come to mind. There's a great chocolate factory in Perugia. You could be somewhat close to Montepulciano. Not a bad diversion if you have the time. Then, there's some really nice towns in Chianti just before you get to Florence.