Need Advice on Citiy/Cities 6 days only

I’d pick 2 cities within 2 to 2 1/2 hour train ride that you can agree on. Go either north or south. Fly in to one, out of the other. That’s all you have time for.
Example fly in to Florence, do a day trip to Tuscany. Train to Rome, day trip your choice, fly out of Rome

For that amount of time and multiple people, I would plan on Rome for the historic sites, art in churches, the Borghese Gallery (need tickets ahead of time), maybe Ostia Antica. Then Amalfi Coast for the outdoor beauty.

Probably 3 nights in Rome, 2 at Amalfi or Positano and your last night in the city of departure- either Rome or Naples.

Hello dbrook2010, and welcome to the forum!

People on these boards usually count nights not days both for clarity and planning purposes like booking places to stay. Keeping in mind that 2 nights means one full day somewhere.

That being said does the 6 days include your arrival and departure day or do you have 6 full days to work with?
If you don't have 6 full days then I would vote for staying in Rome and maybe doing a day trip - Ostia Antica or Orvieto or (in a long day) Pompeii - to break up the time in the city.
If you have six full days then I agree that you could do 3 days in Rome and then 3 days somewhere else.
I would vote for Florence with a Tuscan or Pisa day trip if you can fly out of Florence or nearby like Pisa.
If you have to have the coastal experience you could also do 3 days in Rome and 3 days in Sorrento which is Amalfi coast adjacent without the hassles of AC travel back to the airport and offers day trips to Pompeii. If you were to think Sorrento I would look into flying out of Naples.
My slightly off-piste suggestion would be Venice. I love Venice and it is unique in the world and I think it is a magical place to visit. It would mean 4 hours on the train from Rome but it would only be one way if you fly out of Venice. (Tip: Don't fly out of Venice too early - getting the airport can be a hassle even though it's very close.)

Hope that helps, have a great trip,
=Tod

How many nights will you be in IT?

Sorry for Confusion, I took out our travel days so we have 7 nights and 6 full days. Flying in from Fla.

If you can fly into one place and out the other i.e., Naples / Florence that would be best but if it creates an additional connection than flying in and out of Rome then don’t bother. There are direct trains from Fiumicino Aeroporto (ROM) to Naples (Napoli Centrale) departing at: 9:38a arriving in Naples at 11:33a and again at 9:53p arrives in Naples at 11:56p: https://www.trenitalia.com/en.html.
There’s also a direct train from ROM to Florenze (Firenze SM Novella) departing at 1:53p arriving in Florence at 4:11p. If these times don’t work then you’ll need to take the train from ROM to Rome and transfer there to get to where you’re going.
If you fly out of Rome then spend time in Rome at the end of your trip. Make arrival day a transportation day.
Florence is more convenient to visit than the Amalfi Coast transportation wise. If you go to the coast, you’ll need to transfer to the Circumvesuviana commuter train that’s located in the basement of Napoli Centrale: https://www.sorrentoinsider.com/en/naples-to-sorrento-train-schedule.
If you visit the coast get an early start the morning you're seeing the Amalfi Coast. You can catch a bus outside the train station that fills up quickly. If you are unable to nab seats on the right facing the driver then wait for the next bus. Take the bus from Sorrento to Amalfi where everyone gets off. Make sure you wear motion sickness bracelets on both wrists. This is a hilly road that manuevers around a lot of curves. Take a ferry back to Sorrento.
If you go to Florence buy tickets for the Uffizi Gallery two months out to guarantee reservations. You need a minimum of three nights for Florence, two nights for the Amalfi Coast and four nights in Rome if you include Vatican City.