I would not attempt to drive in Florence. There are way too many areas that are off-limits except to locals, and it’s very easy to get a ticket. When you get a ticket in Italy, it shows up in the mail months after you have returned home and you wouldn't even know you did anything wrong. Even for Lucca and Pisa, I would just take the train if you are close to a station. The train station in Lucca is just outside the wall and extremely convenient. The one area where I would drive is through the heart of Tuscany where you can stop at some of the small medieval hilltop towns. The scenery in Tuscany is beautiful, and usually, the smaller communities are less crowded, and it’s easier to park. The best way to experience the scenery in Tuscany is definitely by car, but to experience it’s larger communities I would utilize the train.