Going to Italy

This is going to be my first trip to Italy and Europe. I'm going to spend about 4 nights in Rome, 3 in Florence and 2 in Venice. One of those days I'll probably spend visiting Modena (Ferrari museum and Pagani factory) and Sant' Agata (Lamborghini museum).

I wanted to get some recommendations from locals or people who have visited the areas in terms of shops, restaurants, and other things to see besides the usual things tourists go to see in those cities.