Not my forte' ... but the hand position seems a bit more demure than the look on her face. Not sure if this is supposed to be a "tough girl" with such a searing look in her eyes or a "pretty girl" who has forgotten to smile.
Maybe another way of saying it. The hands look posed ... she looks real. I'm diggin' the real part, just wish the hands had a more natural vibe that matched the attitude/look on her face and the wind in her hair. Maybe a touch more negative space above her head wouldn't hurt, and possibly a sliver off the right side.
Here's a possible crop to rebalance a smidgeon and some light blur tossed at her hands to try and reduce the attention to them. To me, this girl looks like she's intent on going places ... diggin' it.
BTW, the small version you posted here doesn't do justice to the original size on Flickr.
Agree with Rusty that hands "look" posed. In addition, the railing, because of the significant angle, is not a stable support for the hands and body. It feels like the hands might slide off, creating a tension. Bunched fabric on right shoulder could be photoshopped out. Nice job throwing the background out of focus. Pretty cool earrings!
I am horrible with portraiture but this one seems to have some issues even I can see. No catchlights in the eyes. Flat lighting..actually a hint of lighting from above which leaves an unattractive darkness under the lip and slight racoon eyes. Looks very posed with no moment, no gesture, no spontaneity. Brightness of the hands and upper chest draw attention away from the face. Looks like she is a cute, young girl but this photo is not very attractive.
Sorry if I tend to be overly blunt but this seems average at best.
I like the use of the diagonal, although the relative brightness of her arms and hands tends to draw the eye way from her face. Consider darkening selected areas of the image to better focus attention on her face.
For your the second image, be wary of shooting from too close to your subject and from a level well below her eyes. Both tend to distort the size and shape of nose and chin in an unflattering way.
Eyes are shaded in both shots. That occurs outdoors because dominant vector of the light comes from high overhead in skylight. The solution? Bring a ladder or find a higher POV so you can have the subject look up to get light in the eyes with the camera looking down at the same angle.
Full face pose is square to the camera and nicely symmetrical. The angle of the lighting, directly over the nose, complements the symmetry.
In the oblique pose she's turned nicely to the light, except for the shaded eyes, but the camera was too far around to the right to create a symmetrical look. Her chin around the mouth is disappearing and the nose is starting to block the edge of the far eye. Oblique angles are more flattering when you find good balance between the eye, nose and chin seen beyond the mouth.
Pose the face up into the light then move the camera around to find the best looking balance.
+1 @ foreshortening effect nose, chin, arm in second image ... making them seem disproportionately larger. Foreshortening is a very powerful thing, but atypically does it have flattering results in portraiture. Notice how her near arm appears about 2X-3X times larger than her distant arm. Symmetry & proportion are hallmarks of how we perceive people aesthetically. Exaggeration (i..e foreshortening) typically goes contrary to that aesthetic. A little longer FL or a little further back from the subject would have reduced the foreshortening effect. Which lens was the second image shot with (WA presumed, guessing around 28-35)?
Yes, this was shot with a Sigma 35 and maybe abit too close. I'll take this into account (as well as the other tips) when selecting the remaining pics from the shoot. Should I post additional pics in this thread or create a new thread?
Near / far size distortion is a function of shooting distance not FL. It is noticed more with WA lenses because photographers move closer to crop in camera.
If you use the same 35mm from around 8-9ft the head in the frame will be smaller, but the proportion of nose to eyes and ears will seem more "seen by eye" normal.
If you use the 35mm and shoot tight close-up, H&S, 3/4 and full length crops in camera from different distances you'll see the shape of the face change.
When I shoot portraits I look at the face through the lens at various distances starting from a baseline of 8ft and find which is most balanced. That varies with facial angle and shape of the subject's face.
The "conventional wisdom" to use 85-150mm for portraits comes the days of 35mm SLRs. The reason that range is ideal is because from the "normal" looking distance of around 8ft an 85mm will produce a loose H&S portrait and 150 will create a tight face only shot from the same distance.
I shoot most portraits with my 24-70mm zoom on a 50D crop body because once I find the ideal distance for the face around 8-9ft I can capture full length and H&S from the same spot by changing the FL. Doing that from the same spot changes the crop without changing the perspective of the face.
Also, here is another from the same set. 
