On a tight schedule - About how much time should I plan for the Medici Chapels and the Bargello Museum? Already have tickets for the Accademia and Uffizi and want to try to squeeze both of these sights into my visit.
I have a friend who can spend an entire day in a museum. I, on the other hand, can't be in a museum much over an hour without going into sensory overload. The Bargello is one of my favorites; I spent about an hour there. You know yourself better than anyone else knows you. You don't want to fly thru lots of museums just to say you've been there. If time is short, choose one or two and savor the experience.
Both of those places are definitely worth a visit, not only for the art, but for the way that they are laid out. And the crowds at the Bargello tend to be very small, unlike the Uffizi and the Accademia. (Watch out for the hours of the Bargello - I seem to recall that they're unusual.)
We truly loved the Bargello. Seeing Michaelangelo's unfinished Pieta was the highlight (art wise) of my trip. That being said, on a tight schedule it can be done in one hour, and when we were there mid May there were no lineups. Can't help with the Medici Chapels as it didn't work out for us.
I went to the Medici Chapels when I was in Florence last month and probably spent about an hour there, that included the crypt and the church next to them. If you are short of time I would just go to the Chapels, I didn't mind the others too inspiring. The Bargello I would recommend longer though. It's my favorite museum in Florence and to 'do' it properly I think you should allow more than an hour.
There is a lot of construction going on at the Medici Chapel right now so it's not a great site to visit. I was really looking forward to returning to this chapel because it's beautiful, but the way it looks now I just wouldn't bother. The Bargello is excellent - bear in mind that they're currently doing restoration on Donatello's David. You can see them working on the sculpture but you can't see the sculpture that well. That's a shame because it really is the marquee sculpture in the museum.
As an alternative you may consider the Duomo Museum. this was a great museum, very enjoyable. You can get nose to nose with Michelangelo's Pieta (his last one) and Donatello's Mary Magdalene, with very few other tourists there to interfere with your visit.
One will find the Medici Chapels, the Accademia, and the Bargello even more interesting, if you take the time to read Irving Stone's 800 pg book, The Agony and the Ectasy, on the life of Michelangelo. I think anyone going to Florence and Rome will enhance their visit greatly by reading this book.
We visited Accademia and the Medici Chapels in one morning. It takes about an hour to go through Medici Chapels, yes there's scaffoldingin the chapel of the Princes, but not around the Michaelangelo's. I made a reservation, but didn't need it. No line. You can pick up a quick lunch at the Mercato nearby. I would also recommend the Duomo Museum.
Vi: Do you have your sightseeing organized by area/neighborhood? Doing this will make it easier to see more things. For example, the Bargello and the Medici Chapels are across town from each other. So if you're planning to visit the Piazza Vecchio - do that Bargello at that time. It is a very peaceful (meaning not crowded with hordes of sightseers) museum with some of Michelangelo's and Donatello's works as well as the original bronze panels from the competition that launched the Renaissance!
Do see the Duomo Museum - it was my favorite. The Medici Chapel is breathtaking in how it illustrates the Medici extravagance, but right now half of it is covered in scaffolding - broke my heart. However, the spectacular Gozolli fresco in the Medici's private chapel located in their palace restored my spirit.