I agree to some extent - it's why I eventually stopped reading Star Trek novels. I used to love them, but they fell into this trap where every little detail had to be explained with a trilogy. I exaggerate, but I've always been slightly surprised we didn't see a "Picard: Why He Drinks Earl Grey: the Quadrilogy" (complete with a Janeway appearance, and a cameo by a 300-year old McCoy).
Your post reminds me of something completely off topic and trivial, but I have to get it off my chest. Greg Cox forgive me if you're reading this, but there's this part in the Khan prequel novels where he is in a submarine on Earth, and he exhibits "two dimensional" thinking during a battle. I suppose it's meant to set up the later battle scene in Wrath of Khan where Spock notes that Khan is thinking in two dimensions. But the whole point that Spock is trying to make is that Khan is thinking two dimensionally because although he's intelligent, he's
inexperienced. By having Khan
experience a submarine battle in the novel, it essentially undermines the character in the movie because then his two dimensional thinking becomes a intellectual
flaw, not a matter of being inexperienced.