Hold on a moment, I meet all three of your criteria (if you count shoddy eyesight as a disability). Does that mean I get to be in charge of the next new Power? Woot!
Speaking as someone who's openly trans-female I'd argue that in *some* cases we would know, and while I agree that adding a trans* character to the roster 'just because' would smack of tokenism as you put it, I'd also temper that with the point that in a world where discrimination on the grounds of gender identity can be assumed to be non-existent, it would then be absurd to assume that openly trans* folks aren't just a touch more visible.
On the greater subject of the thread in general, I'm in two minds with regards to the whole skin-colour issue. On the one hand I can agree with many of the posters who've argued that skin-colour will, to some degree, have been diluted by the year 3300 as a natural result of the continuing intermingling of people of different shades and the breaking down of socio-ethnic barriers, but on the other hand I can also see a strong argument for the existence of certain (possibly small) groups of people trying to keep their bloodlines 'pure', as it were, and only intermingling with others of their own ethnic background. I do think that the average denizen of this imagined future would be far more accepting of differences than us twenty-first century humans generally are, but I don't think prejudice will have been entirely stamped out either, though that could just be the cynic in me that's saying that...
You are correct, prejudice will still exist in 3301, indeed it does exist in Elite, it's in the lore, it's been part of the game since 1984. It's now aimed at where someone is from, not what color someone's skin is. Previous Elites that showed faces showed mixed racial features on those faces, it's been stated for well over 30 years now that racial purity will cease to be a thing within the next thousand years among the general populace, it will only exist, if it exists at all, among small cadres of racists, and that's it.
Some of the most beautiful people in the world today on the media are what race? Go take a look, check the Victoria's Secret catalog, instagram, twitter, various magazines, and tell me what race the beautiful people are. Racism exists, it's real, some of us see it and experience it daily, others only read about it and that's their only experience with it. But it exists because racists MAKE SURE IT EXISTS!
Who actually gave any thought to this subject in Elite Dangerous before the OP? What was the point of the OP? To make us aware of a situation that doesn't exist because this is a fictional universe where race was long ago displaced as the reason people hate each other, something the OP and many of those trying to support his cause weren't even aware of?
People who are actually opposing racism already know that words have no effect on racism, it simply doesn't work to tell a racist they are wrong, no matter how many times you say it, no matter how you word it, it has no effect. Racism is taught, it's not innate, it's not natural, children of all races will play with each other without any regard to other children looking different, they do NOT care, it is NOT an instinct, it is TAUGHT. You can only show racists they are wrong by example, time and time again that lesson has been hammered home by racists around the globe, from the white racists of the US Southern States to the Japanese people in regards to all non-Japanese people, you can talk all day long, it makes no difference what so ever.
And people who bring up racism where it actually doesn't exist, every single time, they are racist themselves, and they'll scream and yell and call you all sorts of things when you point that out, cause they aren't racists, they ARE the minority! Worst racists I've ever meet were minorities, every single time, because it's worse with them, they KNOW what it's like to be treated differently due to their skin color or facial features, they decry it high and wide, and yet...they do it themselves. I've seen black people call other black people high yellow or pale skinned, ebony or african black, they are racist amongst themselves, all while screaming loud and proud about how they are not racists and it's a sin and a crime...when people who are NOT black do it to them that is, it's ok when THEY do it to people of any color at all because, well...because they aren't racist!
Racism is a nasty thing, and it's a taught thing, and the only real way to fight it is to simply not do it yourself and lead by example. You won't be winning any war of words with racists, logical, rhetoric, they don't work with something ingrained from childhood and reinforced by family, friends and community. It doesn't matter what color your skin is, lead by example, treat all people based on their actions and nothing else, that's it. It's not that hard to do, really isn't, just remember that every person you encounter is another human being, look them in the eyes and ignore the rest until you know them by their actions, because that's all that matters, who we are is shown by our actions, and our true selves are shown most in our actions when we think no one is looking.