Spoilers for book 2.
I'm at the section now where Detta thinks that all white men want to do is rape or laugh at black women, or laugh while they rape them. Hard to envision Roland as a hate crime rapist when it's Elba in your head. Unless he's wearing white face, which honestly I just don't think would work.
I have no doubt Elba will do a fantastic job but it's just a little strange as I'm only getting into the story at this point on the beach and for me it seems like a crazy amount of character growth to ignore altogether.
It's also crossed my mind that with all the crazy shit that happens that O/detta sees them as different people. Especially in the form of Detta who isn't the most sound of mind.