The Vito in the novel and film were slightly different. IMO, the Vito in the novel was colder. I wish Coppola had included the scene of Vito telling Sonny, "You never interfere between a man and a woman." That comment made it seem like Vito thought he wouldn't protect Connie because she became Carlo's responsibility as soon as they got married. I think Mama felt the same way. She too told Sonny not to intefere when Sonny got on Carlo's case about telling Connie to shut up at the dinner table.

You're right about the Vito in the novel. He did think it was okay for a man to beat a woman if there was a reason for it.