Uffizi has a room full of Botticellis, which is my favorite room. Everyone loves The Birth of venus, but my favorite work of his has always been La Primavera (my favorite composer is Antonio Vilvaldi and The Four Seasons has always been my favorite piece to play when I played in the orchestra, so maybe there is a theme...). If you go, I would say do not buy the advance tickets online. The fees are outrageous. Just go when they open or at 4PM to miss the crowd.