Ok, this is my first go at writing a critique, so sorry if I'm not very good at getting my point across or if I sound to mean at any stage because I do love this image.
Wig: It's a lovely wig, with a vibrant colour. Since Asuka's hair changes all of the time across the NGE series, there's absolutely no fault here. The one thing I'm personally not fond of is how the fringe is cut. It's a little bit too blunt and to high up.
Costume: I love how you did the skirt, it's very full and lovely. The bodice is also very nicely form fitting. From what I can tell, I can see no flaw in your construction.
Makeup: I... really don't like how you've done your make-up at all. It doesn't really say 'Asuka' to me and is overall quite odd. I think it'd be better to go for a much more natural look, as at the end of the day, Asuka is meant to be 14. While you can still keep the eyeliner, it'd probably be better to keep it closer to the waterline.
Pose and Facial expression: I love your facial expression! But the eye make-up just ruins it for me! The pose is very Alice In Wonderland-y and is simply lovely.
Overall: This is a lovely photo! It's almost pin-up in it's nature, and I'm sure people who aren't familiar with cosplay would enjoy this piece due to the composition. The colours work really well together, and the pose and expression are wonderful. Well done to both photographer and cosplayer