Many people head to Piazzale Michelangelo to capture good shots of Florence from above, and the rather dull square is indeed suitable for that.
However, by walking a little further up the hill to Basilica San Miniato al Monte, the view of the city is even better. From there, you can include a few classic Tuscan cypress trees in your panoramic shots (see the attached image).
The fact that there’s also a picturesque church and an enchanting cemetery at your photo spot certainly doesn’t hurt, does it?