Let's see .. where to start?
First of all, I've gotta give a stern wag-of-the-finger for shooting on railroad tracks; in most areas it's illegal and in all areas it's dangerous. (okay, I'm a bit of a hypocrite here, I've done it; we've all done it)
The exposure looks good. Shooting in direct sun is always tough, but the skin is exposed properly which is the most important thing. 45-60 minutes later might have given you more dramatic and interesting lighting. White balance looks good too; slightly warm which is good for most flattering portraiture. A cool WB might have worked better for a zombie shoot; warm works very well for pinup style though.
On composition. I like the line of the train tracks, but to be honest it's a bit detracting from the model. Additionally, the model takes up such a small portion of the frame! She's on the verge of getting lost in there.
On posing. Not bad, some of the basics are there, I might have had her put her left hand (camera right) on the widest part of her hip, to emphasize the curve of the waist and hip, and bend down and in a little more. The sword (I think it's a sword?) isn't quite right - it conflicts with the lines of the tracks, and the backlighting makes the blade so slim that it' hard to figure out what she's holding at first. Or, as an alternate pose, maybe have her lean in toward the camera and use the free hand to hold the glasses, peering over the top edge of the frames.
The poles in the background have gotta go. A couple of quick swipes with the Photoshop healing brush would get rid of them. Or the Lightroom spot-healing tool, or the new Lightroom healing brush.