Does the novelization described Kirk, Spock and McCoy's motivations?
Perhaps not in the way you are looking for. It goes into more detail about what we see on screen. It also gives us more information on why Spock is not 'enticed' by Sybok's gift. Perhaps that's something that you can say hearkens all the way back to TMP and Spock's encounter with V'ger. One of the few things that seemed to carry over from TMP to TWOK was Spock's discovery that logic is not the end of wisdom, but just the beginning, and he finally finds peace between his human half and Vulcan half. The novel does a good job explaining that the reason Spock does not follow Sybok is he has found that peace, and he has also made peace with Sarek. It does a much better job explaining why Sulu, Uhura and Chekov follow Sybok. It actually describes their 'pain' to us as well, and how Sybok is not a true villain. It does a better job explaining their motivations. I don't recall all the details there, though in Chekov's case I do recall it was him being forced to follow Khan in TWOK (and makes him reluctant to 'betray' Kirk in TFF, though he comes around).
I understand Sybok's motivations but what I wanted to learn more about Kirk's motivations, his son was murdered on Genesis where his best friend Spock was resurrected, I can imagine the conflict there. If the planet didn't explode the same process could've happened to David. What happened to Spock was a miracle, it was something Sybok and everyone in the story should be talking about, he's the elephant in the room, Damian!!!
Sadly I don't recall that it does that fully. The book does a lot of things, but that it does not get into that a whole lot. The closest the novel gets is when Sybok approaches Kirk to share his pain, Kirk is keenly aware of what Sybok is likely to expose him to. The death of David is still an open wound and Kirk does not want to relive that. Partly it's because it was a traumatic experience for him. He just made amends with David and then David was murdered. But partly it really is because Kirk realizes, as he says in the movie, that pain is part of who we are. But as we learn in TUC, he still has not dealt with the loss adequately, not until the end of TUC when he finally lets David RIP.
I'm trying to recall if anything of Spock's resurrection shows up in the novel in the way you ask, and I just can't think of anything other than the little bits we see in the movie. He's still adjusting in some ways, but we saw that in the film as well.
By the time they reach 'Sha-ka-ree' their motivation becomes one of simple curiosity.
Spock should be as intrigued as everyone else and would be conflicted between his loyalty to Kirk and his brother.
I think again, the novel does a good job here explaining that Sybok really doesn't know his brother anymore. Spock has grown since Sybok last saw him and his encounter with V'ger changed him forever. His resurrection probably changed him in other ways as well, and is a major event, but like I said, that's a story line that the movie just doesn't get into. I agree, there was more that could have been done with that. V'ger was a life changing event for him, so should his resurrection. But by and large, other than still adjusting, it's basically Spock as he was before his death.
How about McCoy, the movie touch on the illness of his father but it's not enough, I would love to know if he was conflicted between science and his faith. None of these interesting issues many medical and science professionals go through all of the time was never even invited, a tale like that should be the heart of the movie.
Maybe a bit. In the book McCoy is torn because he is a doctor, and a son. He is sworn to preserve life but he wanted his father to retain a shred of dignity and he decides to let him go. The tragedy is a cure for his father's disease was found soon after. That was something that haunted McCoy since it happened, something he never shared with anyone. So it's more a conflict between his duties as a doctor, and him being a son.
As I mentioned earlier, the climbing of the mountain and falling was a nice foreshadow for things to come and was never explored, and finding God within is a cop out and a betrayal of the concept because the journey and its obstacles and what surrounds them should've been the meaning but we have to see something.
Yeah, unfortunately the movie didn't do a good job tying that together.
The movie demanded a divine intervention sequence to occur and it was never approached??? Maybe the novelization had those things, you know the elements of having faith.
I'll have to reread the novel again sometime. I really don't recall how much of that the novel gets into. I'd be curious now to see how much it gets into more overtly. I haven't read it in years and only recall certain things about it.