16 day France and Italy itinerary - please review

You are aware that the Olympics are in Paris next summer, and will be impacting the city, airport, etc, by June?
For Sorrento/ Amalfi, do a Search here, as it's a weekly topic, and there's a wealth of info already posted. You also would get more responses if you posted under the respected countries, or under General Europe.
Have a great trip!

https://search.ricksteves.com/?button=&date_range=2y&filter=Travel+Forum&query=Olympics+Paris&utf8=%E2%9C%93

If you plan to rent a car for any portion of the trip, you will not fit 7 people plus luggage in a minivan. You will need a full size 8 seater van (like a Ford Transit/Tourneo) or two vehicles. Cars will give you more flexibility in Tuscany, but will be a big pain in the cities.

We traveled as a group of 6 last summer. We had a Ford Tourneo. It was a beast to drive & park. It is not easy, logically, finding accommodations, restaurants, etc. for a group that size. Know that you will need to split up at times (taxis, etc).

Carefully consider your lodging choices so people can explore on their own (if willing) and everyone is not joined at the hip. We split our 3 weeks between a couple stops where we were all in one apartment, and other stops where each family/couple had separate hotel rooms.

What mode of transportation will you use in both countries? I agree with flying from Geneva to Naples.
I wouldn't stay in both Annecy and Chamonix. Instead, sleep in Chamonix and take a direct bus to Annecy for the day (1h 45m).
How do you plan on getting around the Amalfi Coast? Praiano doesn’t offer ferry service. Capri, Sorrento, Positano and Amalfi does though.
Will you rent an SUV for Tuscany?

If you decide to stay in Annecy, be sure you have air-conditioned lodgings there (as elsewhere). It can be quite hot in the summer.

I would agree with basing somewhere on the Amalfi or Sorrentine coasts which are served by ferry; you're going to want to use them. I wouldn't choose Capri for 4 nights simply because it's not a great base for exploring elsewhere; you stay there if planning to stay put. I'm also not a fan of Positano due to expense, the many, many steps involved to get much of anywhere, and lack of things to do. Look at Sorrento, Salerno (although Capri is a really long ferry ride from there) or Amalfi. Sorrento and Salerno are also served by rail from Naples (and to/from Pompeii) of one sort or another.

A car on the coast during high season has been roundly discouraged due to very dense traffic and limited parking. As well, during the busiest seasons they've been limiting the days you can drive a rental car according to even-odd numbers on the license plate:

https://distrettocostadamalfi.it/wp-content/uploads/2023/04/Distretto-Turistico-Costa-dAmalfi-Traffic-Regulation-in-Amalfi-Coast.pdf

So the more options you have for getting around via public transit - ferries, SITA buses (which are very busy) and rail - the better. With a group your size, if may also be worth the price of hiring a driver for a day trip.

If you are flying home from Rome, you'll want to be IN Rome the night before your flight. Tuscany is too far away. So you're not planning on spending any time in Rome?

And one more note regarding a vehicle: do your homework about driving in Italy if you've not done so. While a vehicle can be a plus in the Tuscan countryside, you cannot drive it just any old place, such as into historic city centers. Download the free "Driving in Italy" guide linked in the website below (scroll way down the page) to read up on ZTLs, traffic signs, speed cameras, etc. You also don't want to leave anything you can't afford to lose in an unattended vehicle.

https://italybeyondtheobvious.com

Thanks to you all for the questions and tips. I'll take this back to the fam and we'll chew on it a bit. I'll likely reply again in a few days with a revised itinerary and more details. Thanks again!

I second staying in Chamonix over Annecy. We debated the same in early July 2022. Ended up spending the day in Annecy on our way to Chamonix. Annecy was lovely but very crowded. A day trip was all we needed. We loved Chamonix. My husband and college aged kids can’t wait to return.