All I see it lacking, is some finer detail on the clothing, hair, face, eyes and accessories (yes, I realized that is pretty much all of it) and a fine layer of shading and highlights. Then add in an appropriate background that fits it, and it will start to look pretty good.
As it stands, I have a few ideas I'd be willing to work into it, but it is your work, not mine.
Oh, and if those blades were meant to be Japanese in design, be aware that all japanese blades have a slight curve to them, they are not perfectly straight.