These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Ensemble Darkhorse: Aloysius. There was a fair bit of brouhaha when it was thought he would be absent from the movie.
For those who aren't familiar with the book and who are curious who Aloysius is - he's Sebastian's teddy bear.
Ho Yay: The intensity of Charles and Sebastian's relationship were vague in the book but purposely amped up for the movie. The miniseries made it very obvious.
Blanche and Sebastian are even worse.
Values Dissonance: Cancels itself out in terms of attitudes towards Charles and Sebastian's relationship. In the time period when the book is set, homosexuality was taboo, butromantic friendship between men was still somewhat accepted. Thus, people tolerate the boys' friendship, not because they are accepting of homosexuality, but because they do not see it as homosexual.
The Woobie: Sebastian is a beautiful and lively young man at the beginning of the novel, but his family betrays him, his best friend betrays him, his lover is taken from him by the Nazis, and he spends the rest of his life as a hermetic hanger-on at an isolated monastery, with plenty of alcoholic misery along the way.