Yes, Florence can be packed with tourists all year round. Yes, you need to stand in line for a good hour to be able to enter a museum. Yes, you would need to make a hotel reservation well ahead of time. However, once you are in front of the Duomo, or the bronze Gate to Paradise, or Michelangelo's David, all those hours spent dodging people and waiting on line are forgotten. Florence is a city that lives and breathes art and it's well worth all the troubles with the excess of people that you can find there at all times. I would suggest investigate as much as you can before travelling to Florence so that you know what you are looking at and the whole artistic and historical values of the wonderful masterpieces that you would be looking at. And be patient on queues!! Once you enter the museums, you will forget that you spent hours on them