1- I like this composition, this shot "feels good" to me. Probably a more head-on or even top down shooting position would have been more flattering. If the focus was on and the white balance corrected, this shot would be my choice of the lot.
2- This composition works as well, but the busy distractions being them keep pulling my eye from the band. I understand the idea of "in studio" for musicians, but maybe choosing a few of the instruments and having those in the shot would have been a better choice. The cables and wires are my main distraction. Other than that, there are harsh shadows from the flash, and it is out of focus.
3- Not in focus, white balance is off. I think it could be improved by shooting lower and including the guitar he is playing in the shot. Without the strap and the small peek of guitar, I would have just thought this was a shot of a guy from an unflattering angle.
4- White balance, focus...

I'm sounding like a broken record, aren't I? Sorry hehehe. I like the idea behind this shot. Maybe including both hands in the shot would be an improvement.
5- I tried a shot like this once too, and it didn't turn out as I had hoped. I love the idea of drummer *through* kit, but I think pulling back a bit and including more of the kit and stopping down so that it was more focused would be better. As it is, the blurry bits of cymbals in the foreground are distracting and confusing to the viewer. Also, white balance and focus...
I hope I am not coming off too harsh. I just want to explain what my thoughts are when seeing these shots, and maybe provide some helpful ideas to encourage you to keep trying. I think you have some great, creative ideas and I think they can be fantastic if you keep working at it!