Shooting some young models - C&C if you like

[PrestonS]

Few shots of some young models in downtown Detroit. Always wanting to learn more so I welcome and C&C. Thanks.

#1 - Feel like maybe a turned up the reds a tad too much in this one. Not sure on the crop either. Keep the blue sky/clouds or crop it out? I also wish the girl on the right was not looking at the camera.
1/200 f/8.0 18mm ISO100

#2 - This one might be my favorite. Think I could have cleaned up a few other spots on her face. Not sure about the crop on the right side either.
1/160 f/7.1 35mm ISO100

#3 - I like the full size shot of the girl but think the coloring is off a tad compared to #2. Also not sure if I should crop out the red brick wall on the right.
1/160 f/8.0 18mm ISO100

#4 - I like his expression and the way he stands out. I left things a bit dark to match the expression on his face. Not sure if that leaves things feeling underexposed.
1/160 f/18.0 28mm ISO100

 

[KBM1016]

I am not really liking the lighting on these. I am also not the right person to give any sort of suggestions on fixing lighting either, hopefully someone else will jump in and fill that gap.