One of my issues with TMP stems more from the fact that the film is so overtly Spock/Kirk oriented that a lot of what they do in the film could easily have been done by the other crew members.
For example, the scene where the Enterprise comes under attack by V'Ger. I would start it out just as it did in the film with Spock telepathically feeling V'Ger's puzzlement over not getting a reply from it's attempt to communicate with the Enterprise. However, where things play differently is that after the Enterprise survives the first attack, it's UHURA who figures out that Spock was correct and that V'Ger was communicating in a means they didn't pick up immediately. I would than have her be the one who programs her communications computer and transmits the message just in the nick of time.
See what I'm saying? The one area of the film where communications plays a key role in over coming an obstacle in the story, and they don't give it to the one character who's sole job is communications. Watching the Special Longer Edition of the scene where the Enterprise first comes under attack is almost embarrassing since all she does is try in vein to contact Starfleet command. Why? What are they going to say? Good luck?
Absolutely agree. They short-changed Uhura and let Spock take over her role too much. It made sense thematically because Spock is supposed to be in a similar psychological stage as V'Ger, but it disrupted the ensemble atmosphere. I know there's debate as to whether Trek was ever supposed to be ensemble, but by that point that's what people expected to see.
Spock also undercuts her somewhat in decoding the whalesong in Trek IV.