A little necromancy here, but hey, it's not like this particular area of the forums is too active anyway.
I've always thought that nobody in TNE should ever be totally evil, nor should anyone be totally good. In particular, people who are otherwise sort of vile but have some admirable trait(s) about them are great fun.
For instance: An Aubani humanicentrist who, ironically, represents a district of Schalli. The Schalli there have very strong traditionalist leanings, and the humanicentrist actually feeds these impulses by telling them that they're right and they shouldn't really be trying to copy humans and should find their own way. Both sides are happy - the Schalli have a human on "their side" as they see it and the human can work towards his vision that the RC should be a human civilization. However, he doesn't actually support the more ugly forms of Solomani dogma and so forth - he'd actually repudiate them. He simply believes he has an enlightened position that different species have different needs and wants and to try and forge a nation out different groups like this is pointless and that everyone should be segregated into their own "pure" nations and conduct affairs from there. His own biases would come about in subtle ways, like if the players have any members who aren't human, he'd do his best to sit as far away from them as possible, or perhaps meeting with the party in places that require stairs and have no lifts or ramps (to hinder Schalli rollers), burning incense at all their meetings with a Schalli smiling apologetically that he dislikes the "fish stink" of the recycled water in the roller (but of course, that's not a problem of the Schalli who can't help the way they are, he'd hasten to add). On the other hand, despite his ugliness when it comes to racism, no-one can deny he's done plenty for his constituents. He's successfully developed a sailing yacht club (with himself as a founding member), organizing races, development of maritime traditions, and so on. At the same time, he has instituted a very steep "noise tax" on speedboats and similar modes of transportation that offend Schalli sensibilities. The two factors combined have basically made speedboat racing and similar "noisy" occupations a thing of the past. In addition, he's pushed hard for the popularity of "naturally caught" seafoods as an export from his district to help the "back to nature" Schalli earn money if they wish it. He's discouraged (or outright shut down) maritime industrial pursuits such as deep sea mining and so on in his district, instead replacing it with a thriving resort trade catering to fellow RC functionaries and families as he (correctly) reasons that most humans only use the very surface of the water and stick close to shore, away from the Schalli. The Traditionalists also like the fact he doesn't try to make apologies for being human and going for swims with Schalli or any of that other "me too" humanistic bullsh*t - when he meets with them, it's through vid and his meetings with them are very concise, well-explained, and best of all brief which means that the Traditionalists don't have to use the hated technology more than necessary.