first of all: congrats for beeing an aunt now. I know how you must feel, I became an uncle a few months ago (my sister got twins!).
I really like the design of this fighting elve. For the hair (which as far as movement goes is pretty cool,) I'd agree with kinjark. If you do it a bit more detailed it would really enhance.
I would not agree with Elwell about "Her entire action is thrusting forward...", I did japanese sword fighting for about 3 years and think that the position of her body is perfectly believable. The upper body can lean forward, while the arms cut back, so the position of her hair is absolutely correct, when this represents the moment just after having made these sword cuts. (At the beginnig of the cutting action she is supposed to have leaned even a bit more forward)But concerning the slice you should change it as Kanji2000 proposed ("It's plane should be almost parallel to the ground..."), because this would be the logical position of the blade.
Otherwise it's really cool and I hope to see it coloured.
"Happen to every guy sometimes this does."