I don't think a proper John Wick game could be a third person shooter.
John Wick doesn't aim. His reflexes and muscle memory are so superior, that lining up his aim and acquiring targets is not something he needs to think about and thus something the player should have to think about. Crowd control is the challenge John Wick faces so it should be the challenge the player faces. Reacting to the existence of an enemy threat is what you should have to worry about, not lining up a shot. If John sees them, they're shot. (Unless they're another assassin.)
I say again, it would have to play like an evolution of the Arkham combat. I just don't think there is a game like that yet.