Ebert is sure entitled to his own opinion, but in this case, I think he is being a little lazy when it comes to this film.
When talking about why Michael ends up lonely he says,
But what was his sin? It was not, as we might have imagined or hoped, that he presided over a bloody enterprise of murder and destruction. No, Michael's fault seems to be pride. He has lost the common touch, the dignity he should have inherited from his father. And because he has misplaced his humanity he must suffer.
That is correct - Ebert answers his own question. For Michael it was all about business. He kept telling himself that, and that he needed to do what he did to keep his family safe.
And it didn't really matter what kind of life he took up for himself. If he would have been a legit business man, a CEO,, perhaps he would have let business interfere in his life too, and still he would have alienated everyone he loved because he was a shrewd businessman. It happens all the time.
The flashbacks give Coppola the greatest difficulty in maintaining his pace and narrative force. The story of Michael, told chronologically and without the other material, would have had really substantial impact, but Coppola prevents our complete involvement by breaking the tension. The flashbacks to New York in the early 1900s have a different, a nostalgic tone, and the audience has to keep shifting gears. Coppola was reportedly advised by friends to forget the Don Vito material and stick with Michael, and that was good advice.
Yeah and if he would have stuck with that advice, FFC probably wouldn’t have won the best picture and best director award and De Niro definitely wouldn’t have won the best supporting actor award. And the movie would have been half as ambitious as it was.
Here is where I strongly disagree. While only Michael’s part of the story would have been fine and well, the flashbacks add to the structure of the film, and definitely don’t take away from it. if anything, they add another dimension to Michael's struggles in the present. If Ebert could understand and appreciate the juxstaposition that FFC used in the baptism scene in Part I, why can't he understand and appreciate the same themes in Part II? I think Ebert is being lazy here. In his review of 21 Grams he also says that if the movie were in chronological order, it would have worked much better. I thought it worked great as it was.
Perhaps Ebert would enjoy the Epic. That way there would be no flipping back and forth between past and present.