I thought the Great Khans were presented as one of the most ambiguous factions in all of Fallout history. They're a bunch of drug dealing murderous criminals but they're a decent sort to each other and a family. Well, except, of course for the fact Bitter Root says they were abusive assholes he was glad to see killed. They were very well developed, IMHO, as a multifaceted group of criminals who were still human beings. Of course, the badassery of the Khans is downplayed and I think we're meant to see the GK at the Twilight of their power (potentially). The Bitter Springs massacee have already reduced the Khans to a shadow of their former selves just like Mojave BoS and Enclave. They're anachronisms that will continue to fall to NCR and irrelevance unless they get the hell away from them.