I agree, I think he did a good job with the supporting cast in keeping them happy.
It would have been bad if any had jumped ship because they didn't get their little spotlight scene.
I was more commenting on the folks who think that somehow under nimoy their roles were big or substantial. Yeah, for the most part in TSFS & TVH they got 1 day each if they were lucky where the focus was on them.
I gotta feel bad for the folks whose favorite character is, say, Uhura and they think she had a decent role in TSFS because she had one scene with 20 lines and had another 20 throughout the rest of the movie!!