Imho...godfather iv if made should definitely be made like two...but like puzos desire, it should contrast santino at a young age to vincent as don. In the flashback scenes, I would definitely make it to show the very different personalities of sonny and mike. The highlight of the movie would be a scene that convinces vito in a "what would a good leader do" type of way that sonny probably wouldn't make a good don but michael definitely would.

A famous killing scene would be how sonny made his bones by killing someone who loved his infant son so much...and the slight carlo type of violence could come with kids picking on fredo and sonny coming to the rescue. Id also like a little detail on connie and michaels relationship. Maybe even a rosanne's kids type of dislike for eachother...only to show michael and connie knowing they are all eachother has in their dying years.

In the current part of the film, the point michael tries to express with no breath left to vincent is that he can't let his temper control his decisions. That he must stay resonsible and act in a business over personal type of mindset.These scenes are what parrallels the young sonnys temper scenes...only to try so hard to not lose it that he ends up losing it one time and it cast a huge mistake. Id like for a traitor to be in the film...who is now a traitor by wearing a wire and will be star witness to vincent losing his temper.

But the traitor is secretly an fbi agent and get this... he's the infant son to the father that sonny had made his bones with. Id never put it out there in a corny way where the guy is like "your father killed my father!" Type of fashion. Ending the movie, I would have scenes depicted from the sonny scenes showing obviously that he was the little infant in the movie...almost like a Usual Suspects type of "ah ha" lightbulb for the viewer. This will fade into vincent looking out a small pen window just like vito was looking out the ellis island window as a child.