You used a pretty grainy film, right? They have a lot of soul. I like them a lot. Look like they could have come straight out of the 60s.
A couple thoughts, Most of them are from about the same height perspective and angle. Most of them tend to focus on getting the whole of the individual playing the instrument. They're all pretty straightforward and approximate the same compositional themes and attributes. I'd say you should really mix it up. Get close, get high, get low, do some more abstract compositions, focus on just a hand, or an amp, or something small, and let everything around it fall into place before you shoot. Just get experimental. Some shots just won't work, but at least you tried.