Overall, great movie. Not sure if it's going to top Voyage Home for me, but it's certainly competing for the slot. Good characterization, good action-adventuring, and the right amount of humor. (An awful lot of beard stubble though.)
Yet I can't help feeling there was something missing. At first I was thinking it was the science, but.. there was that red matter timey wimey wormhole stuff. And the entire plot was definitely a science fiction plot. So it wasn't that.
I've tentatively come to the conclusion that what was missing was the 'figuring stuff out', or, to put it another way, 'thinking'.
Characters acted in smart, clever, and even brilliant ways. But the thing is, all their cleverness was in the form of instinct or sudden inspiration.
They couldn't get a transporter lock on moving targets. Except Chekov: "I know how to do this!" Brilliance and a skill that he had already developed. They need to beam onto a ship in warp. How do they solve this? Ambassador Spock hands Scotty the algorithm. Scotty is stuck in some fluid-filled conduit. Does Kirk figure out some way to get him out? Not really.. he just happens upon an escape hatch to trigger.
Kirk and Uhura hand Pike some information to indicate that the problem with Vulcan is a Romulan attack. That's some figuring out, but mostly it's convincing, with a side order of amusing.
Spock, at least, realizes that he seems to be the key to this Romulan attack. But nobody really sits down to figure this out either. They don't realize there's an Ambassador Spock out there that maybe they should find and talk to. No. Kirk just amazingly, incomprehensibly, coincidentally, bumps into him. Which we can chalk up to Fate or the timeline trying to fix itself, but mostly eliminates the need for anyone to figure anything out.
And at that point, it's just Ambassador Spock telling Kirk what he needs to do and leaving it up to Kirk's instinct after that.
So, all in all, no thinking. No, coming up with Reliant's prefix code. No, listening to this weird alien message and figuring out they should listen to what it sounds like underwater and then recognizing it as whale song. No hair-pulling, nail-biting, thinking desperately to come up with a solution time.
Mostly it's, do what your gut tells you to. And when that fails, do what Ambassador Spock tells you to.
Not that it's not a good movie with the ending I hoped for, for all that.