Finally making first visit to Italy after a 2 year delay

Arrive 16 may for a week in Montepulciano then 4 nights in Florence. How easy is it to bus from Montepulciano to other towns for the day? With only 4 days in Florence, please tell me the one thing that I need to see or do other than the Uffizi and academie. Also do you reccomend the Firenze card to insure minimum waiting for entry to museums?
The Firenze Card is not being sold yet, so you will need to decide which museums you want to visit and buy ticket for each. I would recommend booking ahead only for Uffizi and Accademia, they have long lines always. Others you can just go and buy ticket on the spot.

It isn't that easy to bus from Montepulciano but you can make it to Pienza and from there to San Quirico and maybe to Montalcino but you'll need to be super careful with schedules. You can also head to Arezzo and Cortona with bus.