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.
Fair for Its Day: Exaggerated, this book shows such an enlightened viewpoint that it would not be out of place in modern times. Especially in its praise of Islam, it is hard to imagine that it was indeed written during the British rule of India.
Harsher in Hindsight: Aziz comment on the religious divisions in Indian society that "We may hate each other, but we hate [the English] more", which is eerily prescient of the bloody, sectarian partition of the Subcontinent during the independence process.
Ho Yay: Between Fielding and Aziz. It is very easy to misinterpret the last 3 paragraphs of the book as an erotic encounter between them, also, particularly as Fielding based Aziz on a close Indian friend with whom he did indeed fall in (unrequited) love.
Mary Sue: If Fielding is the mouth piece through which Forster verbally expresses his views, Aziz is the living painting by which those views are validated. The man is utterly morally flawless, commits no grandiose or unjustified acts of malice (the closest thing he gets is a few strong words to Fielding at the end of the novel and his general annoyance at him comforting Adela, who very nearly destroyed him), is a highly intelligent and incredibly well versed doctor and is described as athletic, handsome, and physically strong to boot and with the patience of a Saint. Now compare him to the mean spirited, bigoted, hypocritical and cruel upper-class Englishmen who persecute him.
Aziz is irresponsible, petty, sexist, and overly concerned with looks. He has a lot of good qualities, but he's hardly a Sue.