The first couple are definitely a little dark and a little cold looking. It's a different look, and I assume it's deliberate, but they don't flow with the rest of the set.
#3 is an idea that doesn't work for me, too much uninteresting crap in the background.
#5 is a problematic pose, unless you're shooting porn. Normally the model tilts one shoe out, to get more of an innocent "what, me?" pose to balance the "here's my crotch" thing.
#6 is a little odd. Why is she out on that side of the frame? Also, why does it feel tilted?
Overall, quite good stuff, these are just my quibbles and complaints.