That is a REALLY neat (if kind of freaky. ^^;) 
idea. Her wig and ears are perfect.

I think it'd be more effective though, if she 
weren't smiling. Chi always seems to have that 
completely blank wide-eyed expression, and when 
I think of her, that's what comes to mind. To 
have a doll smiling so hugely makes her feel 
less like Chi. To me, anyway. Also, I think it'd 
be even more amazing if her wardrobe were base 
on (or close to) the outfits from the 
series/manga. ...Of course, that would probably 
be much more costly to you, money and time-wise.

I don't think I, personally, would buy it... but 
I definitely give you credit for thinking of and 
creating her. That's a trully cool and unique 
idea. I hope you make a lot from it. ^^

-katie