Wow, so many names - it's not easy to replace MP ...!
Victor Garber would be great - but not available? I really liked him as Sidney's Dad: always concerned but tough-minded, too ...
Someone who crossed my mind: Gregory Harrison (you remember "Gonzo" Gates?) he has this intensive charisma (now in his fifties) and fits very well!!
But I'd LOVE to see Ray Liotta in CM ...! He's just perfect for this kind of character! Obviously he's busy with filming *sigh
And please add me to the Ron Livingston fan list (yes I know *sigh* Hotch and him would be too similar characters
Best wishes from Germany (sorry for my English)