I just saw the film again on the big screen and marveled at how great it is overall, but I'd be interested to hear people's thoughts on the following:
1) The entire opening sequence is supposed to take place during the reception for Connie and Carlo's wedding, as the Don hears requests from various people in a room in the house. But even though the film keeps cutting back to the raucous reception in the garden, with a band playing, for the most part it's completely quiet in the room where the Don is holding audience. The only moment we hear some noise from outside is when Johnny Fontane arrives. I guess this is just done for effect, but it's not realistic.
2) The character Sollozzo is present in that scene where Luca Brasi is garroted to death, but then very shortly thereafter he and his cronies abduct Tom Hagen in midtown Manhattan. How long afterward is that scene going to take place? And come to think of it, an awful lot happens on that one day, including the gunning down of the Don.
3) One of the most unforgettable scenes is the one where the studio head, Woltz, who has refused to grant the Don the favor he asked, wakes up to find the bloodied, severed head of his prized stallion in bed with him. But seriously, how credible is it that the Don's goons could have gained access to the bedroom of Woltz's L.A. mansion and somehow placed the severed head of his horse under the covers where he's sleeping without the guy waking up? Again, I guess it was just done for effect and we're not supposed to ask questions like this.
4) Sonny is shot to death on the causeway, on his way to Connie after she has called to tell hi that Carlo has beaten her up again. At the end of the film, we're told that Carlo set all of this up. But how? Are we supposed to think he beat up Connie because he knew she would call Sonny and he would immediately drive to meet her? And even if that's credible, how did the men who killed Sonny know when he would be at the causeway, and that he would be alone in the car? (As it is, he's being followed closely by some bodyguards in another car.)
5) While we're at it, why did the Corleone family allow Connie to stay married to Carlo -- and, for that matter, why did they allow Carlo to remain living -- after he had already beaten her very severely at least once while she was pregnant? Yes, I know it was the 1950s and divorce was a no-no, but I would think the Corleone's would have figured out some way to deal with that.