I'm sorry if this has been discussed before but in a deleted scene and after Vito was hit, Michael tells Sonny to check with Vito on how the family should proceed. Michael does not agree with Sonny's approach.
What would Vito have done differently if he was still able to give the order? Perhaps he would have negotiated a truce and Sonny was too hot and taking it personally basically pushing the family to start a war. Perhaps he would have negotiated with the other Families? I don't know.
What would Michael have done? Maybe Part 2 Michael may have not killed Paulie outright and instead used him to feed him false information and to find out who was behind it all - Barzini.
What do you think?