No problem with the Black guy its the white girl that I have a problem with. Star Wars was always at its core through the entire first three movies about the relationship between sons and there fathers. The broken unresolved jagged wound of the Vadar, Leia relationship is also central to complete narrative of first three movies.
The concept was so appealing that the next three movies went back and told the story of the father. But lacking the conflict of the father, son relationship of the original movies they were far less appealing. The conflict between Luke and Vader was the driving theme of all the good Star Wars movies. Now we get a hunger games fifteen year old girl as ether the Luke are the Han of the new movie while the Leia role has vanished in order to make room for giving the older characters screen time.
They will very likely regret there casting choices for this movie. Someone is going to get fired over this. They will ether reboot after the first film or there will be a white boy joining the cast as a main character in the second movie.