The photos look pretty good. They are a bit dark, which can be attributed to your slow lens. If you are going to continue shooting this look into getting a faster lens. If you had enough reach with the kit lens you may want to look into the 50 f1.8. That way you can get your aperature down more to expose the pictures better. It's a $70 lens and everyone should have one in their bag. I use mine a good bit for indoor portraits with available light. The depth of field is really shallow at 1.8, but you could get away with 2.8 and still get a good looking shot. You could also invest in a shoe mount flash like the 420EX or 550EX. I have the 550 and it will light up a room better than I though it would. Bounce it off the ceiling and you won't get those rough shadows and that "deer in headlights" look.
Otherwise in the shots, they all seem to have a guy standing over to the side, which to me is distracting. Something I learned reading a graphic design book is an object that stands on it's own away from the group will draw attention. Try to cut out the guy as AP did with his crop.
Otherwise, I think they look extremely painful. I hope I never find my body in that position unless I'm on a wakeboard. I hope the floor is padded.