SUPER ARISA WORLD

[NICKtendo DS]

Looking at the sprite, I think another problem might be her cream yellow skin. It's merely an observation, I'm not saying it needs to be changed, but it affects the design in a way.
The color makes her skin look like, well, skin. From Arisa, we know she is a bullet, because she is a parody of Gilbert. We have to assume Belle is a bullet, because she rivals Arisa. What the color does is make her look more human than intended. It's an issue you might take into consideration if you're going to work on her design. Again, not saying you have to change the color (though it might help to choose a different yellow, but that's up to you).
I think look and feel wise, she needs a feature of her own, because she doesn't look 'special'. Arisa has her pigtails, Sengi~ her antennae and extra arms. I tried to add a distinctive feature when I was drawing my version, like the hairclips. Perhaps just adding something as small as that is enough.