Homosexuality: There's actually a lesbian character Nora Treadwell, the old lady near the lake. She doesn't volunteer this information, but if you ask about the name she mentioned, she says it's "her wife". So, pretty Pozzed given the time period.
British empire diversity: There's not one, but TWO (and possibly more) east Asian characters: Mr Josh Gladwin Moon, who's Korean and Professor Chiyo Kogawa who's Japanese. I don't think the British Empire had much interaction with Korea or Japan at the time. It would actually make more sense to have a Chinese character or two, given the opium and tea trading and all that. Moderately Pozzed.