Anybody with half an ear to pop culture will know why Star Trek's original series was so revolutionary for its time: it had the most racially diverse cast, what with Sulu and Uhura, and then there was Chekov on the bridge during the Cold War.
So when I went out to see the new movie, I kept my eyes peeled to see what the racial representation was like. After the white-washing in Avatar, I needed to see proof that yes, Asians and other PoC are still valuable persons in how we envision the future. I wasn't disappointed. Yes, I was slightly disappointed when Sulu whipped out the sword and it looked vaguely like a katana - he used a fencing foil in TOS, despite the director's suggestion he use a katana, and I really liked the idea better. (Also, my father fenced in school. I sort of wish he'd made me take fencing lessons instead of piano lessons.)
So I like Star Trek for giving me Sulu and Uhura. I like Voyager for giving me Chakotay and Harry Kim. (And have I mentioned that I watched Voyager during a time when I told my friends, "I've never met an Asian man I'd like to date, so that's why I don't date Asians", and it was a half-lie because there was an Asian man I wanted to date except he was a fictional character in a scifi show. Sorta burned.)
There have been very few other shows since then that attracted me for its diversity except Star Gate SG-1. I was drawn to the Goa'uld Yu, who didn't pose as a god, but as an emperor. Also, the concept of creation myths being at the hands of aliens was also very well handled. (This is where I'd ask myself, is this cultural appropriation? And I say no.) On one planet which is a free Jaffa village, I noted that most of the background characters were PoC, starkly contrasted against the background characters at the Cheyenne Mountain base who were white. As a TV series, it certainly did its best to bring the greatest variety of ethnicities to the small screen as possible, even though you could still tell that majority = white. I appreciated that.
But by and large? There hasn't been many good scifi/fantasy shows out there which, to my knowledge, seriously does the concept of racial diversity any justice.