For every meaningful detail I infer you think is in the book but not in the movie, I think there are innumerable meaningful details in the movie that are not in the book. I'll stick with big, obvious examples here which I hope we can all agree on. Is it too obvious to point out the book doesn't have music or sound effects? Is it too obvious to point out the book is black text on a white page and the movie is in color? Is it too obvious to point out the book is static and the movie is, yes, a motion picture? You imply music and sound effects, color and motion and much more are irrelevant. You refer to them as "atmosphere". How quaint. Oh, yes, I disagree your comment.
If all you want from the movie is its plot, then ..., well, even then the book and movie diverge. It's all about those pesky details which you think are "critical". Well, let's see how gosh darn critical they are. E.g. the mission in the book is to Saturn; the mission in the movie (and strangely enough, in Hyams' movie and Clarke's sequels) is to Jupiter. Someone goes to the wrong planet, don't they? Do the characters in the book or the characters in the movie go to the wrong planet? Your "critical details" boomerang on you. For a reason I do not understand, you imply the movie is somehow incomplete or got things wrong and that Clarke fixes everything, that Clarke and not Kubrick was in charge of the project. Hogwash.
Please tell me how the book explains the movie, how the book supplies "critical details" we need. As much as I enjoy the book on its own terms, I don't need its "critical details" to help me enjoy or appreciate the movie at all and I don't think anyone does. Every time--and it is weekly if not daily--that I read someone claiming the book helps a viewer with the movie, I wince. It implies there is something horribly wrong with the movie, that e.g. Kubrick was incompetent, was unable to depict Clarke's vision or had no vision of his own. Why bother to watch the movie? Do you not see this?
"[...] omitted for the sake of style" is hilarious.