Gaal and Salvor are both white men in the original stories, unsurprisingly. Spartacus and I watch the show and joke about how fast Asimov is spinning in his grave at all the changes but I think they did a really good job with the adaptation -- visually it's stunning, and it has much more narrative push, especially in the early sections where really, not a lot happens except some guys standing around talking smugly at each other. I also hope it gets another season.

(It is really very loosely based on the novels, though -- especially in season 1 I kept having to stop and think, "wait, isn't this the actual opposite of the point of the novels?")