Not my favorite Trek movie, but, yes, Spock's character arc is one of the best and most lasting parts of the film. He's supposed to be colder and more remote when he first rejoins the crew--to the extent that Kirk and the others are somewhat taken aback by his aloofness. It's not until after he mind-melds with V'Ger that he comes to term with his emotions and warms up again, becoming more like the Spock we remember.
And this changed attitude is arguably the one bit of TMP that carries through to the subsequent movies.
And getting back OT, the movie now suffers in comparison to KHAN, but I still have fond memories of seeing TMP on that opening night long ago, in a theater packed with thrilled Trekkies who had been waiting years to see Kirk and the Enterprise again.
And this changed attitude is arguably the one bit of TMP that carries through to the subsequent movies.
And getting back OT, the movie now suffers in comparison to KHAN, but I still have fond memories of seeing TMP on that opening night long ago, in a theater packed with thrilled Trekkies who had been waiting years to see Kirk and the Enterprise again.