My DH is really disappointed that T.C. is playing this role. He read all the books. When he discribed J.R. to me my first thought was Dwayn Johnson( THE ROCK). He has the size and ability to pull this character off with great appeal.
My 2nd choice would be Liev Shriber. Not so much bulk but very good actor and has played parts like this.
I hope the movie is better than we may think with T.C. in the lead.