You could make the special effects look better than Star Trek XI if you threw enough money at it, but it'd still be the movie where Spock's previously unknown (and never mentioned again) emotional Vulcan brother captures the Enterprise with the power of positive thinking so he can meet God.
Well, I suppose that's true. But how many Star Trek episodes hinge on some equally convenient introduction of a character, technology or other such thing that we've never heard of before and never have mentioned again? Quite a few, I think.
And, to be fair, Sybok did not capture the Enterprise by giving motivational speeches. That was the veneer he put on it to make it look noble and good. But, in reality, he was using his telepathic abilities as a Vulcan. It's not like Sybok just gave a speech about God and suddenly the entire crew decided to mutiny. He used an advanced form of telepathic brainwashing. McCoy says as much.
And, lastly, I'm not sure why so many people have such a problem with the "searching for God" aspect of the plot. Sure, we all know that the Enterprise is not actually going to meet God. But there have been plenty of crazed, mentally questionable religious zealots down through the years who have believed in things equally ridiculous. Do you recall a group of people being convinced to commit suicide so that they could join the spaceship that was hiding behind a comet? So why are Sybok's motivations any more ridiculous?
In fact, that was Shatner's point. He was commenting on the many televangelist scandals of the time. To show how easily people's good motivations with regard to religion can be twisted and perverted by a charasmatic personality into something sinister.
