The sound score
When I first saw it back in the late 80s, I thought it was one of the cheeziest, crappiest scores made for such a fine film, but I was only a kid then. I saw it again a couple of months ago... and the music IS cheezy and crappy! Abel Ferrare shoulda done some more edits to include better music, some Italodisco, some New Wave, or at least some Muzak to have some variety in the movie. The film could easily be one of the best of its genre if the score was changed to something that can tie it to a specific time and place - 1979/1980, New York.
Do The Mussolini! Headkick!