Early Trip Itenerary-Can I get a quick sanity check/opinion?

It appears that most of day five will be consumed by checking out of the hotel in Venice, getting to the train station, going to Florence, getting to the new hotel, and checking in. And it almost always takes longer to that than anticipated. As a result you'll have very little time in Florence before heading to Rome. That being the case, I think I'd skip Florence entirely and concentrate on Venice and Rome. Don't mean to be Debbie Downer, just offering food for thought.

I think this sounds like a very nice itenaray for 7 nights. Good job! Have fun.

To clarify, we don't plan on going into Florence at all. We were just going to catch a tour or driver there to head through Tuscany towards, instead of hiring one all the way from Venice where it would likely cost much more.

Looks great, but I think you might have difficulty with finding a wine tour on a Sunday. If you could rejiggle your departure dates or Itinerary so that it was on a weekday you will have lots of choices. I was just looking at private wine tours and they are not cheap, like 800 EUR and up for 2 people.

You can do this with a slight modification since wineries are likely to be closed on Sunday. On Day 5, just take the train straight to Rome, check into your hotel and spend the afternoon in Rome. On one of your remaining days, you can take an all day wine tour to Tuscany from Rome. Here is one such tour for your consideration. I'm sure there are others available.

https://darkrome.com/rome-tours/tuscany-tours-from-rome?utm_source=bing&utm_medium=cpc&utm_campaign=DR%20-%20US%20%7C%20CA%20-%20Rome%20-%20Food%20%26%20Drink%20-%20%5BE%5D&utm_term=tuscany%20wine%20tours%20from%20rome&utm_content=Rome%20-%20Tuscany%20-%20Wine%20-%20Tours%20-%20%5BE%5D

I wouldn't book a cicchetti touron your first night (or indeed anything for your first night) until you arrive in Venice and see whether you can stay vertical that late. If you've been to Europe before and know you'll sleep pretty well on the plane, feel free to ignore this advice.

If your departure date is set, then Stephen's suggestion looks to be the answer to the puzzle.

If you can shift your departure date, then your "do it on the way through" could work and save you the backtracking time of a tour from Rome

With so little time in Rome I would do my own enoteca tour in Rome...seriously...that wine comes from Tuscany too! LOL
Generally speaking, jet lag, lots of walking on hard stones, and the train ride from Venice to Rome is a lot....you may not want to sit on a bus or whatever for a full day Tuscany tour

I am not a fan of Rome, but have family there, so I do go there every other year or so, but 3 nights would be the absolute minium that I would recommend to a first time visitor.

Tours by Roberto http://www.toursbyroberto.com/ You may have luck with them on a Sunday, I booked a Sunday tour (Chanti). Click on the calendar link. Good luck, I think it would be a nice way to see Tuscany, even if it is brief.