The hair could use some low-lighting - a little bit of dark. It's too bright solid yellow. Maybe it's "accurate" that way but I just don't think it looks quite right. I don't know how to accomplish this, though - if it were solid or even fabric, you could give it a quick rinse with a very dilute dark-brown paint wash, and the wash would collect in the recesses and give it texture and definition. But if it's a styled wig, that definitely won't work. I don't know.
That Fenrir keyblade in your Sora album is flippin' sweet - did you make it?