25 days in Tuscany (mostly)....suggestions and feedback, please.

It seems you are not interested in spending time in Bologna. So, If you can drop the car off at Piazzale Roma and not on the mainland, Why don't you drive up to Venice? Bologna station is a labyrinth.

Is there any restaurant/taverna guide available for the area that might point us to great out-of-te way places to stop for lunch or dinner?

There is the SlowFood Italian Osterias guide and it's the best. I don't know if they finally translated the app in English. Try to click here on your iPhone and see if you are redirected to the English version:
https://apps.apple.com/it/app/osterie-ditalia-2021/id1544039902

These days a fake taverna is a place for hipsters. A real taverna was a place where aged guys went mostly to drink cheap house wine, curse the government and blaspheme God.

some local event or specialty to explore

While driving around, look for amateurish, small billboards saying: "Sagra del... [add a local dish]" or "Fiera del...]". Be aware that some local dishes far from the tourists' path may be a little...surprising!

Thanks Dano. Will check into that app. Actually we are interested in Bologna. But my house swap for Venice was only available first week in August, so headed there first. Then back to Bologna for 6 days, Milan for 6 and Lake Como for 12.

Will check into driving all the way to Venice and dropping off car there!

Although Tuscany is crowded in the summer, a car is very helpful in visiting the smaller and the less-travelled towns. Only because your car-time is limited, I'd mention that Orvieto is a very easy visit by both car (giant, mall-like parking garage) and by frequent train. San G is not so accessible (but greatly over-touristed anyway.) I'm not suggesting that you rearrange your plans to hit Orvieto by train, but just point out some nuances.

Siena parking can be quite far (and well downhill) from the sights and/or your sleeping location. This can be true in other Tuscan towns. You may have to drive around as if you are in a mall before Christmas, waiting to see someone pull out of a spot.

You are seeking advice, so I should not criticize you for listing such big tourism sites as you did in the "Questions" paragraph. There are some tiny towns that are just gems, worth a one-hour stop. Here's a raw list I worked from. Of course we couldn't see them all:
Siena MW, Spoleto, Assisi, Perugia, Orvieto, Montalcino, San Gimigiano MH, Pisa, Volterra, Castellina, Radda, Volpais, Vertine (fortress), Badia a Coltibuono, Greve MSa, Castello di Brolio, Arezzo, Panzano MSu, Colle di val D'Elsa, Sant'Angelo in Colle, Pienza, Monteriggioni, Montefolloinico, Cortona, Castiglione del Lago.

We chose to have our big meal at fine-dining lunch restaurants at wineries (pre-payment often required, arranged by our hotel before arrival), and a bar snack at our out-of-town hotel for dinner. Note that you may be hot and tired and sweaty by 4PM every day. I never thought I'd look forward to a swimming pool every day!

When driving the curvy back roads of Tuscany be sure to stop at little bars/cafes in little no name crossroad towns. We had some of our best interactions with local people. That included coffee, drinks and simple local food. Be sure you are not anywhere near a tourist spot. This can’t be done without a car.

We found that taking the bus, taxi or walking is the best way to eat and spend time in central Siena. Parking and potential for traffic tickets is horrendous there.

I'd never drive to Siena, but you can always park in the modern town and take the public escalators up to the historic district on top of the hill.

Trying to find a parking spot up there has been a nightmare since Dante's time.

Do not leave anything in a car parked close to a tourist attraction. Never. Visible from the outside or hidden in the trunk makes no difference.

Thank you all for your advice and help. In the driving portion of the trip, we plan to park wherever it seems safe and convenient, drop our stuff at our home swap and then do our touring on foot for a day or two. Then, we'll head off (without luggage) for any nearby towns that sound appealing. On days traveling from one base spot to another, we'll make sure our luggage is confined to the trunk of the car and not visible, when we stop en route.

Many thanks, Tim, especially for the list of appealing smaller towns. That's exactly what we were hoping for! I hope we'll manage to get to at least a fair number of them!

Melissa

Just be aware that your luggage can be stolen from a locked trunk. I've read of it happening several times, but I can't say I have not taken the risk myself.

Near Lucca/Pisa, check out Pistoia and Barga.
Pitigliano is really great, but if that does not work out there are some cute towns nearby.

we'll make sure our luggage is confined to the trunk of the car and not visible

I don't want to be too negative, but you are looking for troubles.

Even if not visible, it will be obvious to anyone you are non EU tourists driving a rental car around the countryside. A thief could break into the trunk in 30 seconds just to check if there is something inside.

These thieves have no ID, no country to be sent back and no criminal record: they couldn't care less of security cameras, but your all vacation will be ruined.

Of course I hope am wrong and It's true that most times nothing bad happens in parking lots.

OK, so about the luggage. What are tourists supposed to do? Yes, we'll leave the luggage behind whenever we can. And we won't be traveling with a lot, in any case (one small carryon each). But is it really so unsafe/stupid to leave luggage in the trunk when you are moving from one base town to another? We can't stop for lunch and a walk around a town without worrying? Or we have to drive nonstop from Siena to Asissi, to drop off our luggage at our new abode before we can walk around and grab a bite to eat? I'm not talking about parking the car in the middle of Florence, or Siena or Orvieto for that matter and leaving it for hours with luggage in full sight. Come to think of it...Im going to post this question on the Italy forum and see what the advice there is.

But is it really so unsafe/stupid to leave luggage in the trunk when you are moving from one base town to another?

It depends on how much risk you are willing to take. You will run more risks of a car break-in than locals and EU tourists precisely because others before you have ignored the same advice. Unfortunately thieves know it, thankfully there is a thief every 500 tourists.

You are on the right path to take an informed decision, no one can do more than that.

Parking in the smaller towns can be a challenge but I've always found parking outside the walls. Google parking + city name and you will find public lots. Parking in Siena is not difficult: https://en.sienaparcheggi.com/en/1028/S.Caterina.htm

I would ask at each hotel for their parking ideas.

I have not been to Pienza but it's on my list!

Enjoy your trip.

DD

I don't rent cars in Europe, but I'd suggest you take a lightweight tote bag or daypack with you. On the days when you're shifting to new lodgings, put critical things in that tote/daypack rather than in your suitcase before packing the car. Carry the tote/daypack with you if you make a stop before off-loading your luggage. Among the things I'd put in that bag or pack--or in a money belt: money and bank/credit cards (best to divide these between the two of you), passports and vaccination cards, prescription medications, cell phones and tablet/laptop computers, camera gear, prepaid tickets for flights and site entries, and critical itinerary notes. Those are the things I keep in a tote bag at my seat when I hop on a train, because my suitcase may not end up being in my line of sight.

Other suggestions have been offered in earlier threads that drifted into this topic:

• Buy a chain and a padlock when you get to Europe and chain the suitcases together in the trunk. I'd attach the suitcases to the interior of the trunk if there is a way to do that.

• Open the suitcases and strew (valueless) items around the trunk to make it impossible for a thief to grab everything quickly and run with it.