I'm sure Cumby will make a fine Khan. I really don't care what ethnicity the actor is. That's why they call it acting.
Only thing about Khan's blood being used as a cure-all is, why didn't Khan Prime ever think of it? But that's minor, in the grand scheme of things. Just chalk it up to something that Section 31 discovered and leave it at that. Would make it interesting to suggest that Khan's enhanced intellect really isn't perfect after all...
I wondered about that, myself. Could be in this universe, Section 31 has been playing around with his genetics to study him and they've experimented on him, creating the "magic" blood. Khan, humbled to be the guinea pig as he's actually seething and plotting his vengeance. That will be my canon, at least.![]()
The blood reminds me of the magic Cylon/human blood which saved Roslin in nuBSG. At least for awhile.