A few disclaimers before I begin: I prefer to break down works by category in my critiques, as great ideas can be poorly executed (but are still great ideas) and simple ideas can be masterfully executed (But push yourself!). Also, I try to reserve a 5 star rating for truly exceptional work. That said, here goes: Vision: You're trying to present a classic portrait of a beautiful woman. It's hard to convey an actual idea or theme through a portrait, but for what you've done, it works. Mission accomplished, and I can't say anything negative about it. Originality: Unfortunately, portrait shots are common. I'll give you credit, the background fill is slightly interesting, as is the lace outfit, but it's not enough to make this really stand out to me from amongst all the others. Push yourself a bit more to do something truly creative and unique next time. Technique: I had to open the photo in a second window to dissect your technique here. You're using an off-camera flash, high, high camera right, to light your subject, right? I personally disagree with the position you chose for the flash. You've got your model turned towards the flash, creating a short lighting scheme. This makes your already thin model look even thinner than she really is, although, since the flash is right above your head most likely, the effect isn't severe. It does however, give her the dreaded "raccoon eyes"- her eyes are in shadows. Eyes are emotive. You want to focus on them and be able to see them in a shot. I'd have kept her pose, but put the flash a bit lower on camera left, to shoot across her body instead of somewhat straight on. I'd have put a reflector or a second flash on camera right to provide fill light and soften the shadows on her face. Because you're now shooting in a broad lighting scheme, her face would fill out a touch and look not quite so thin. Another point I need to bring up, is that if you're trying for loop lighting (placing the shadow of her nose on the cheek) then your flash is way too high. You don't want the shadow to touch her lips. If you had lowered it to just above her eye level, you'd have less of the raccoon eyes effect and the shadow would be considerably smaller. So, to review, camera flash to the left, fill light, and lower. Other than that, it's in focus and crisp and clean. Nice background lighting btw.
Impact: Despite the lighting flaws, it's still a stunning portrait. It caught my attention and made me go wow enough to write this critique. Good job
Remember when you take a portrait, you're trying to smooth and flatter your model's looks. Overweight people don't want to look overweight (we hate it) and I imagine the really thin don't want to be reminded that they're really thin. Try to place your lighting situations to balance out the look of the model. And push yourself to do something really different!