I have argued for Ray Haffner as Red John,

but,

If we are judging the last seven suspects by the actors playing them, then Xander Berkley ( portraying McAllister ) comes out way on top...Anyone who has seen him in other roles ( like Percy in the show Nikita, or " The Man " in the series " The Booth at The End" ) knows he has the intelligence and subtlety to play a character like Red John...The small town hick Sheriff he plays in The Mentalist almost seems like a waste of talent...but he has played other characters, convincingly, that would be more than a match for Patrick Jane ....

As a director he would be your perfect choice to play Red John....A guy that can play the simple small town fellow....but change gears to emote menace and a top level intellect...