Nubia vs. Nu'Bia
First of all, thank you for posting all the Nubia scans.
I have always found the Post-Crisis Nubia (I refuse to dignify the apostrophe) really problematic and disappointing. Obviously the Pre-Crisis Nubia is a product of her time and is distinctly racially problematic, but there's absolutely no reason why a Post-Crisis version of her couldn't surmount that. VIXEN is pretty racially problematic too, and they've handled her pretty well in recent years (aside from those issues with the 'coloring error').
The major problem with Post-Crisis Nubia as presented here is that, in their attempt to defray tokenism, they made her distinctly not African. The Zoroastrian hokum is dreadful and doesn't fit well with the rest of the Wonder Woman cosmology, but most importantly it has nothing to do with Africa. Making Africans something else entirely is not the correct way to solve the problem of racist depiction of Africans. This Nubia should really be a Persian or Median character; there's nothing African about her at all. Obviously a black character need not be defined by her blackness, but this is a character -named- Nubia. She is figured as a representative of her race and continent by her very name, and that cannot be ignored without raising significant problematic questions.
This is all without getting into the elements of the Post-Crisis Nubia that are otherwise disconcerting, such as the fact that she is profoundly bound to a male character (in a way Wonder Woman certainly is not).
I was pleased to see Grant Morrison use a Nubia character in Final Crisis as an alternate universe's Wonder Woman. I'd like to see a new, post-Final Crisis revamp of Nubia in which she acts as an activist, teacher and warrior for the people of Africa the way Wonder Woman does for Europeans and Americans. She's got great potential as a character and could really be a positive force for representation of Africans in a way DC has never really managed; Vixen is African, but very assimilated into American society, while characters like Impala and Freedom Beast have never caught on.
At the end of the day, I'd also really like to see the Pre-Crisis origin restored. Why -can't- Wonder Woman have a black sister? It sounds silly at face value, but it's a profound and lovely statement on the female condition, in my opinion, and now more than ever I think Africa could use a strong female voice in the DCU. Gayatri Spivak says that brown women are tired of white women trying to save them, and that it is time for brown women to be allowed to save themselves. I'd like to see Nubia take up that mantle.