I can agree with the tattoo, but it would be too detailed to be visible on the model in game. The simplicity of the official tattoo is pretty good.
I don't like the kimono because it makes her look more like a geisha than a warrior. The gi makes her look like a badass, sleek, and deadly.
I can agree about the mask covering her face, but I actually like the kabuki mask better than the flower headdress in general, .. and there is the fact that the kabuki mas is pretty essential for the theme.
The weapon is hands down better in the official splash, you said so yourself.
Even if the textures were updated, and even if all of the other aspects of the character were replaced in the same setting and orientation, I would still prefer the official setting and orientation because it appears very strong and spiritual.
She is a deeply contemplative warrior who is in turmoil. Everything she was taught growing up was a lie and she even had to abandon her family to follow the path she truly believes in. I get more emotion from the official splash than the fan made one.
It's certainly a good piece, don't get me wrong. It is also pretty clear that the official art was inspired by this one. I just feel that the final result is still better.