Do you remember an episode where Uhura was a constant whiner about her relationship with Spock in the original series?
Spock and Uhura didn't have a relationship in the original series (guess why)
however, that didn't stop her from flirting with him on the bridge while they were working and he was the acting captain, and then a moment later she basically called him out on his s**t because Spock was too cold and didn't seem to care about one of his crewmates dying.
She slept around with her freaking Academy instructor and complains to him when she doesn't get selected for the best ship in the fleet.
I think you're mistaking Uhura for Kirk
Uhura does have an exclusive emotional relationship with Spock. Big difference. But if to you their interactions suggest he's just one of the many she's having casual sex with, I don't know what to tell you, honestly, but doesn't seem to me the problem is exactly the writers here.
as for her 'whining': it's funny because Kirk was 'whining' and complaining about Spock way more than Uhura in that movie
Uhura's concern that her boyfriend might possibly have a death wish should be the least surprising thing. If you think that Kirk is entitled to have his own feelings when it comes to complaining about Spock being.. himself
or him not getting friendship, then I can't see why you should have a problem with Uhura having agency and being allowed to speak her mind and express her feelings when it comes to someone she, actually, has a relationship with and who might have a freaking death wish.
Your complains about the scene where Uhura is assigned to the enterprise might hide a bit a double standard too. First: it is obvious in the scene that she had worked hard to get on the enterprise and the only reason Spock changed her assignment was because he was overcompensating to 'avoid the appearance of favoritism'. Second: when all is said and done, you have a Kirk who wasn't assigned or supposed to get on any ship, to begin with, but his best friend abused his position to sneak him aboard the best ship (and even infected him with a virus)
Also friendly reminder that Uhura, unlike some of the guys there, was promoted to chief communications officer because of her skills alone and because she was more qualified than the previous officer
, surely not because the other officer was sick or dead or because Pike was her mentor.