...But at least interesting things are done to them, or told about them, off screen. McCoy is sent off to civilian life, Spock chooses the career of a religious hermit, Kirk loses his soul to bureaucracy and becomes an asshole, Uhura gets a backbone, etc. It's convenient to do "character development" like that offscreen, so that you don't have to write the dialogue to actually show it.
The mission really hanged on a thread, succeeding thanks to a series of coincidences that brought the right people together. And I have absolutely no problem with that. That's realism: when armageddon thunders towards you with just a day or two of advance warning, you have to rely on miracles.
Perhaps another set of coincidences would have saved Earth if the adventure we saw did not pan out. Starfleet might have had other competent people to handle the incident, and other ships that could have withstood V'Ger's initial wrath or cleverly avoided it. That would be realism, too. No doubt there were Plans B, C, D, E and F being worked out as soon as Plan A was approved, and some might have been ready for execution by the time V'Ger reached Earth. It's just nice for us viewers that our very own hero got to do the honors.
Timo Saloniemi