Hi Zazu, I'll take a crack at some C&C.
#1 - the light is too flat (looks on-axis/on-camera) and therefore isn't flattering to her face. Her expression looks like it's between poses, and the framing could do to go a bit lower... watch the fingers getting cropped out. You could have probably brought the top of the frame down to about mid-forehead to make room for her hands, or you could have come closer to her to remove the hands altogether and maintain a good composition.
#2 - I'm not sure if you had control of the lighting on this shot or not, but very well done! I love the pose, I love the framing, and the light on her face/body is very good! My only complaint, and this is just nitpicking, is that I would have loved to see the exposure on her as it is while having the background a tad bit darker. Be it from an umbrella/softbox/snooted flash from above (in the direction the light is coming from) it would make her stand out a bit more. But as I said, it's a very strong photo without anything else
#3 - Good light on her face and her eyes are bright... The space at the top of the frame bugs me a bit though as it doesn't add a lot to the photo. The shapes in the background are a bit distracting, so I would have come down a bit lower with the top of the frame. Cleavage is a bit distracting, I would have likely tried to use her hand or that step to leave a bit to the imagination.
#4 - I don't like where her head is within the frame... I think it should be more towards the top. It looks like you're on the steps still here so I'm not sure if you could have maintained the same angle while moving around but you could always crop if necessary. I'm not sure about the pose, but it isn't
bad. A smaller, more-shallow depth of field could possibly help eliminate some of the shapes in the background as well because the black "blob" in the top-right of the frame is a bit distracting - it's in focus just enough to notice something is there.
#2 and #3 are definitely the best, with #2 being my favourite

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