- Curse of the Black Pearl (Sparrow's island scene with Elizabeth)
The later movies were more egregious with letting the comedic moments overtake the serious moments, but this one was particularly saddening because it is such a defining character moment for Jack. For all the fun that the world of POTC is, this would've reminded the audience that it is absolutely still full of danger and cutthroat people, and Jack has lived in that world for 10+ years now. Just seeing his banged up and scarred body is a sobering realization of what being a pirate is.
Not to mention the moment later on when they talk about how Will is going to die, and Jack just passes her a bottle of alcohol to mourn his likely death. Also the subversion that it was Elizabeth who decided to get drunk and start singing was nice.
- The Avengers (Steve Roger's first scene in The Avengers)
Just a huge missed opportunity. We already saw how he was sad about missing his date, but seeing him look through a folder of his old squad all being dead would have been shit sprinkles on top of his shit sandwich, and it would've been so heart-breaking to see in the full movie.
The following scenes of him being so alone in New York would have been so powerful too, and I suspect it would have resonated with real life veterans as well. It would have been an excellent start to his "man out of time" theme that would be expanded on in Winter Soldier.
- Revenge of the Sith (Palpatine's fight with Jedi Masters)
Not much really needs to be said. The original fight just felt like a bunch of old guys stick fighting while the deleted fight actually felt like Palpatine was a Sith Menace who was easily killing off Jedi Masters.
- Revenge of the Sith (Anakin's fight with Obi Wan)
I get that George Lucas' intent was to depict Anakin as a childish teenager, but Revenge of the Sith was where that should have ended. At the very least, the latter half of ROTS. This isn't to say that the original fight of Mustafar was bad, but compared to that fight, Anakin has a dark aura of calmness in this one. Anakin very coldly choking Padme, then fighting Obi-Wan with an unchanging expression would have been an excellent contrast to Anakin's emotional bursts in Attack of the Clones and drive home the idea that this was not Anakin anymore, this was Darth Vader.
