Unsolicited hot take on the whole damn thing from non-EU fan perspective:
Long ago I had assumed that the sith/empire were meant to be alien-phobic space nazis. They were all human in film canon, and they were all white men with the same accent. Darth maul confused me, awesome as he was, because he wasn't human. He seemed more like an expendable attack dog, which I thought was confirmed when it turned out that sidious was also grooming dooku for apprentice. I think that adding alien/gender/ethnic diversity and inclusion to a military cult of space-nazis was a dumb idea