Some interesting replies here. I would love to address all of them, but that would be long

Suffice to say, there are some fun ideas running here.
I enjoy the movies, overall, but here are my list of notes that I think could help:
Star Trek (2009):
-Slow the pacing down just a little and let all the emotional moments sit for a minute. I love Kirk and Spock Prime's moment in the cave, and Spock and Sarek's moment in the transporter room.
-Keep the section of Kirk and his brother. I think it sets up the crazy ride and crash, and Kirk's arc a little bit better, plus the potential for him having his brother show up at some point in time in a later film.
-Reduce the number of people saved by Kirk Sr. For me, it just makes the Kelvin too big for the time period. It's a minor nitpick, but it still sticks out to me.
-Have Scotty be on one of the other ships that gets destroyed and survivors are beamed aboard. He is in Sickbay while Chief Engineer Olsen leads the away team. Olsen is made first officer under Spock, Kirk second officer as a field commission. When Olsen is killed, the Kirk moves up. Scotty is also tapped to take over in Engineering, and is the one who does the transporter magic to save Kirk and Sulu. Chekov gets introduced by Pike as before, but also has the confab moment of warping in to Titan's moon, giving him and Scotty that time of working together.
-At the end, Kirk offers to help and Nero engages the self-destruct, not allowing his ship to fall in to enemy hands.
-Finally, a montage at the end, of Kirk receiving promotion after promotion and moving him up to ranks until he reports to Pike his readiness to take on command. Pike smiles at him, stands with a cane (indicating passage of time) and tells him, "You want to take on the big one?" Cue to bridge scene.
Not as in depth as others, but my small notes.
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