You know- there is so much advice and info and answers to all of your questions in your various threads already. I suggest you reread them all- ignore what doesn’t apply to your trip.
That said- I like to keep things simple and I am a frequent traveler.
Here is what I would do-
Take 1 night from Rome and give it to Florence.
Forget the Tuscany tour from Rome and drop CT (you are trying to fit too much and a day trip there will not be as enjoyable as you think)
Sat May 27- arrive Rome in the evening
Sun May 28- wander Rome- do the Heart of Rome walk from RS Gide book
Mon May 29 Colosseum tour with Walks of Italy, general sightseeing in the afternoon
https://www.walksofitaly.com/rome-tours/roman-colosseum-tours/
Tues May 30 Vatican tour Pristine Sistine with Walks of Italy, general sightseeing in the afternoon
https://www.walksofitaly.com/rome-tours/pristine-sistine-chapel-tour/
Wed May 31- Train to Sorrento via Naples- can visit Pompeii on the way or visit from Sorrento- less complicated. The transit from Rome to Sorrento is a bit of work and it will be getting very hot at Pompeii by the time you get there.
If you skip Pompeii today you’ll have to choose between Capri and Amalfi day tour. I’d probably skip Capri.
Thurs 6/1 Amalfi day tour with Mondo Guides
www.sharedtours.com
Fri 6/2 Pompeii with Mondo Guides- easy to get there from Sorrento, no issues with luggage OR Capri boat trip with Mondo Guides if you did stop at Pompeii
www.sharedtours.com
Spend your evenings enjoying Sorrento
Sat 6/3 Train to Florence- this will take a good part of the day
Sun 6/4 Sightsee Florence- book your tickets for the sights you are interested in- Uffizi, David, Duomo etc.
Mon 6/5 (museums closed today)
All day guided bus trip of Tuscany- include Pisa, Siena, San Gimignano
Here is one that has been recommended on this forum
https://walkaboutflorence.com/tours/the-best-of-tuscany-in-one-day-trip-from-florence
They offer 3 pricing options- with tower climb, with or without lunch...
Tues 6/6 More Florence sightseeing if needed- afternoon train to Venice- or just get going in the am
Wed 6/7 Venice
Thurs 6/8 Venice
Fri 6/9 Fly home
The above suggested plan keeps most everything on your list, will give you a more relaxed trip, fewer train changes means less stressful transit days.
Rome 4
Sorrento 3
Florence 3
Venice 3
If you haven’t booked lodging yet you need to do that asap- especially for Sorrento.