For Part 3, what they should have done was base it on the missing years between 1927 and 1945. IMO, i think it's kinda ridiculous that they had to create new characters like Vinnie and Hagen's son. We were never told in Part 1 that Lucy got pregnant, and it was never mentioned in the novel. I understand that some new characters were needed for Part 2; i.e. Pentangeli was a substitute for Clemenza, and both Roth and Ola supplemented the story. There was no need to know what happened to Michael and his family by the end of the 70s. We all knew that Michael lost his soul by the end of GF2. So that should have been the end. There's enough material from the novel to cover those missing years. Had FFC went for the missing years to create GF3 instead of jumping to the late 70s, he would have definitely completed the Saga, and all of us would have been alot happier. And there would be no need for GF4. This would have been a better Trilogy than the one we have right now.