no problems, cheers, I hope it helped. Somehow it's much easier to do this for someone else than for oneself - I have just as many quandaries as you and need others help me sort myself out.

The suggestion to flip your trip around was a good one, I agree it would be easier to leave from Rome than Venice. We did Italy after Paris, so arrived in Venice from Paris. However, starting the Italy portion in Venice worked well. We stayed in Venice for a few days, http://venezia.boscolohotels.com
then got a rental car and drove from Venice to the areas in Tuscany we were interested in. Stayed at a fantastic Agriturismo VilIa in Chianti,
http://www.vignamaggio.com/en/
After seeing parts of Tuscany we returned our car in Florence, since driving in Florence is not a good option. If you are considering Pisa, returning your car there, then taking the quick train ride into Florence would also be a good option. We spent a few days in Florence, our Hotel was directly across the street from the Santa Maria Novella train station.
http://www.hotelambasciatori.net/en/index.html
Nice hotel, well priced, and included a great breakfast. It was very conveniently located, walking distance to most all sites. Checked out, walked right across the street and boarded the high sped train to Rome.
Rome Hotel also walking distance to the train station, and many of the sites as well as a subway stop right out front.
http://exedra-roma.boscolohotels.com
Spent 4 days in Rome them flew home from there.
If you are going to keep CT you could add that in when you have the car.
Happy travels.