Composition: For this challenge I cant really see silky smooth. I can see a lot of different textures..even on the skin. The harsh crop across the girls head really doesn't compliment the smooth approach you were after.
Technical: The focus has grabbed onto the girls right arm and hair on that arm. The focus should be on her face more....especially the eye lashes...that would have been a good starting point for the viewer to then be led into and around the image. The lighting and colour is very natural which is a plus though.
Overall: Try a slightly different crop and get right down to the girls level and play around with different shots. Always try to get the eyes and nose in focus as this is where people naturally look to first.