I am really only used to
Leonardo, but I do like some of the other names.
Niccolo is much better then the overly popular
Nicholas, which is quite common in the us, also spelled
Nickolas,
Nikolas...
Damiano is nice, and I also like the form
Damian.
Tiziano and
Fabrizio are interesting but I don't realy like them.
Rocco is sort of cute, it makes me think of a little boy with dark hair and eyes.
Giulio is nice, but in the us you usually hear
Julian or
Julio. Still in Italy, it would be cute on a little boy.
I like but don't love
Caio and
Cesare.