AWESOME! I loved reading this. Great Job.I think Paul often gets undue negative comments because he pushed the band to try different concepts and directions. After all, it was he who pushed the Sgt. Peppers concept, the Magical Mystery Tour TV special idea, the Get Back live band/movie concept, etc. (Not all successful.) In his defense, wasn't he just trying keep The Beatles ahead of the rest of the Pop/Rock trends as they had been their whole career? If the Beatles had simply continued to make albums similar to Revolver or Rubber Soul, the fans would still buy the music (and it would probably be great music) but after 3 or 4 albums of that the fickle public and critics would declare they had gone stale or were just playing it safe. Paul wanted the band to continue to set the bar the rest of the music industry aspired to be...and keep their music on radio and money rolling in.
John & George were becoming preoccupied with other things (and Ringo was just happy to do whatever the other three wanted to do) and they were all wealthy enough to not have to work another day in their life if they wished. Paul still wanted to WORK at being a Pop entertainer and in that limelight. John & George were ready to retreat to their homes and family life and any music they made would be very personable spiritual (George) or political statements (John) and if Beatles fans didn't 'get it', that's their problem. And they had certainly earned their right to live their lives and careers as they wished.
The Rolling Stones could have all retired as multi-millionaires a couple of decades ago - but they still enjoy being a working/touring Rock band. I think that is the same drive Paul has always had (and Ringo re-discovered with his All-Star tours.) And since George Martin wasn't there to help guide the Get Back sessions, someone needed to be directing/producing the process and in the film it is obvious no one else besides Paul seems very interested in anything else but to jam on some old Rock & Roll classics. Just have fun, ya know? When it came to working on the new songs, I think Paul was just trying to do what he thought George Martin would have suggested.
Remember, George Martin only agreed to do the Abbey Road album after the Beatles agreed to "Do it they way we used to do it..and in a civilized manner". He wasn't willing to do another Get Back/ Let It Be affair. And aren't you glad?