Coppola Should have just paid Duvall the amount he deserved instead of just writing out his character. It would have been better if they had Tom Hagen.

Also i think if they had flashbacks like Godfather 2 of Vito in the 30s (Which i think they were going to do in part 4) it would have been better because we would get to see more of the corleone crime business then in the final version