Very nice saber. If anything, I'd say her left arm is a bit off. The upper part looks a bit too thin and/or long, and doesn't seem to connect to where the shoulder should be.
The nose looks a bit awkward (a bit flat and the perspective seems to be different from her eyes and mouth) and maybe it would be fun to try other dark colours instead of mostly black to give this picture more life yet maintain the contrast. Other than than that I like it though, the glowing sword works really well here and its light makes the rest very pretty.
and just when i finished re-watching fate:zero too