Nolan North as Moon Knight
North is best known for his voiceover work as The Prince in the most recent 'Prince of Persia' video game, Deadpool in 'Hulk vs.' and most notably as Nathan Drake in the hit PS3 game 'Uncharted: Drake's Fortune.' As most who have heard his work in these and other voice acting roles would agree, he is an extremely talented voice artist. However, after seeing videos of his acting as Nathan Drake for the filming of the cut scenes of "Uncharted," I noticed that he is also a very talented actor. The limited amount of live action stuff that I have seen on YouTube is also a pretty high quality (General Hospital, Ugly Betty, Six Feet Under) and I believe that he would be the perfect choice for playing a complex character like Moon Knight who has numerous personalities!
Djimon Hounsou as Raoul Bushman
As anyone who has seen 'Blood Diamond' would agree, Hounsou is an amazing actor. Though many would like to see him as another Marvel character, Black Panther (which he would be great at). I think that he would make an even better villain. He has the right intensity on screen for such a villainous role as Bushman. I believe that he also looks perfect for the character.
Donald Sutherland as Dr. Peter Alraune
Unfortunately, I couldn't find a picture of Dr. Peter Alraune, but Sutherland not only looks right for the character but he is also the best choice to play the character that is a big part of why Marc Spector becomes Moon Knight. Though his role is only a minor one, I think Sutherland is a great actor who would really have a great impact in the movie especially the character's final scene in which he is murdered by Bushman.
Jennifer Morrison as Marlene Alraune
The actress best known for playing Dr. Cameron in 'House' would be great for this part in my opinion. She is an extremely talented actress (who you may have also seen as Kirk's mother in this years 'Star Trek') who I believe could easily pull off the many emotional scenes that the character shares with Marc Spector in the characters origins as well as later on being one of his closest allies and sometime lover.
Mathieu Amalric as Jean-Paul DuChamp ("Frenchie")
The French actor known for his role as the villainous Dominic Greene in last year's 'Quantum of Solace' would be great as Moon Knight's pilot and closest friend. He is an extremely talented actor who would be great in this role and I believe that he looks just like the character!
Bill Nighy as Khonshu
Though the character's part would be minor, I can't think of anyone better to voice or even play the role of the Egyptian Moon God Khonshu. As "Pirates of the Caribbean" proved, he makes an extremely threatening villain. So I think he would be perfect as the God who gives Moon Knight his powers and later comes back to goad him into becoming a killer.
So that's it! Let me know what you guys think!