Hmm, I wouldn't say there are any good or bad/evil characters in Claymore. That suggests that the characters are a lot more shallow than (I believe) they are. But if we were going to make that distinction, with clare and crew on the good side and awakened beings and yoma on the bad side, then miata and clarice would probably be neutral
But I personally don't believe there are any good/evil characters, or even a good/evil struggle. Yoma themselves aren't necessarily "evil" - they're just very dangerous - like something more feral and intelligent than a dangerous beast.
The primary struggle is Clare against Priscilla: Clare doesn't fight for good (though she may embody 'good' aspects), she fights for revenge. Isley and Priscilla don't fight for evil, they fight for conquest. (Well, Priscilla not even that.)
The Organisation I think is the closest to 'evil', but not because they're evil but because they're callous, immoral and threatening. Warriors are just the tools of the Organisation to dispose of the pests called Yoma and Awakened Beings (and more recently, renegade Claymores). Clarice and Miata are those tools the Organisation is using to dispose of Galatea - who herself isn't a threat to anyone anymore, though one could argue that she'll eventually become an awakened being and threaten humans, but what's the likelihood of that with her suppressing her Yoki completely for many years? The organisation also claims to be the protectors of humankind and yet demands huge sums of money to render this protection service. I have a suspicion that the Organisation has ties to the origins of the Yoma themselves - like an experiment gone wrong (but maybe not). The ambiguity of the Organisation's origins and purpose make them the most threatening players in the world of Claymore - but, you still couldn't call them evil.
I agree that Galatea chose not to regenerate her eyes. Of course another reason would have to be that it would be much easier to exist among humans when they can't see your silver eyes - because you don't have any.
)... but trust me you will not be disapointed 
I love her new look, she look pissed all the time.
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If she will survive then she will surrely regenerate her arm fully due to her defensive type.