There are many opinions on the movie itself and how it comes across. Personally, I think it's great because you get a look into the Beatles creative process. There isn't any other album they recorded where we get film footage of them creating their music.
It wasn't a good time for the group. They already had a lot of friction during the making of The White Album. Paul gets a lot of flack for coming across as being bossy, but think about it, if Paul wasn't the driving force behind keeping the group going, they would have split up during the making of the White Album. We wouldn't have had any of the music that came after, and there would definitely be no Abbey Road, their masterpiece.
If there is any concerns about how negative this film makes the group look, they could always alter it slightly, by putting an epilogue indicating that the group decided they would set their differences aside to record one final album with all of them fully participating, and that album would be Abbey Road.
Now if the legal issues that keep holding this film up could be put aside and a blu ray with extra footage be released! Anything the Beatles release sells well, they know that, and this movie will not be any exception. They could also increase revenue with a limited theatrical release just prior to the blu ray's release. So many possibilities with this movie. Stop arguing over how to put it out and just Let It Be!