Well, they literally grabbed this guy for Kang:
And Mandarin is nothing like the comics. I'm not too optimistic. Part of the fun was that Kang was similar to Reed and Doom and you had this what-if thing going on with Reed, Reed's dad Nathaniel and Doom. Now that's lost, and most importantly that guy has no regality. I can't imagine him as Immortus. I suspect they did it purely to have a black guy ruling Egypt because now Egyptians are black for some reason. I still remember the hissfit tumblr threw when Rami Malek played an Egyptian. Don't get me started on that Exodus film...