Awesome Music: "Hail, Poetry" from Pirates. Sort of an inverse BLAM. There's at least one great song in every show, but Pirates is particularly strong in this regard.
Comedy Ghetto: There were many critics who considered comic operettas to be beneath Sullivan's attention as a "serious" composer. Sullivan was inclined to agree with them, although it helped that the paychecks he got from the Savoy operettas were far above what he got for his serious classical compositions. Of course, his music proceeded to experience Magnum Opus Dissonance, and these days his concert works are remembered mainly as pieces from the guy who wrote those comic operettas with Gilbert.
Fair for Its Day: The apparent anti-feminism in Princess Ida is nothing compared to the genuine Anti-Feminist jokes of its time. The Tennyson poem it's based on is also arguably worse in many respects than Gilbert's parody, since the Framing Story basically claims it's an incompetent attempt by feminists to rewrite history, which ends up showing that a woman's place is with her man. In Gilbert's version, the worst you get is some characters poking fun of women's education — before they get there, and all of whom think that educated women are fantastic once they meet them, skewering of some of the man-hating aspects of Ida's college, and a scene where book-learning meets reality, and the woman refuses to do surgery which she was taught to do from books alone. Plus, in Gilbert's other work, in Utopia, Limited, the Cambridge-educated Princess Zara never has this poked fun of, and is shown to be vastly more capable than most of the men, so it's not like he makes a habit of anti-Feminism.
In HMS Pinafore, just how old is Ralph Rackstraw supposed to be, anyway? Captain Corcoran has a grown, marriageable daughter. Buttercup claims (Unreliable Narrator, perhaps, to help sort out the mess?) to have raised both Rackstraw and Corcoran as babies and switched them. In fact, if one is paying attention, the three pairings at the end of Pinafore are all disturbing by modern standards. Ralph marries a woman literally young enough to be his daughter, Porter marries his own cousin, and Corcoran marries his own wet-nurse. Ick. At best, if we assume everyone started early, Josephine would be in her late teens, the Captain and Ralph in their mid-thirties and and Buttercup in her late forties. Nothing too bad...
If they're celebrating Frederick's birthday which happens to be in February wouldn't that mean all of the lovely seaside action in Pirates is taking place in the winter?
A notable Older Than Radio example is the "What, never?", "No, never", "What, never?" "Well, hardly ever." exchange from H.M.S Pinafore. The editor of a certain London newspaper is said to have threatened to sack any man on staff quoting the passage, his rant ending with "I never want to hear that joke again!". Cue everyone...
The Mikado in particular is the source of many now-familiar English phrases, such as "a short, sharp shock," "Let the punishment fit the crime," and "grand Poohbah."
Refrain from Assuming: As was common at the time, effectively every song is named after its first line, not its refrain. The only exceptions are the ones where the refrain doubles as the first line (such as "I Am The Very Model Of A Modern Major General"). However, Gilbert himself, in his 1890 collection of lyrics, Songs of a Savoyard, gave each song a short descriptive title instead, e.g., "The Major General's Song" (for "I am the very model of a modern major-general") or "Eheu Fugaces—!" (for "Time was when Love and I were well acquainted").
The story behind Sullivan's popular and beautiful song "The Lost Chord". Sir Arthur's brother Frederic, though trained in architecture, shared his brother's love of music and eventually made a career on the stage. He created the role of the Learned Judge in the first G&S operetta, Trial by Jury, and was quite well received by critics. However, Fred died of liver disease and tuberculosis at the age of only 39, leaving behind his pregnant wife and seven children. Sir Arthur composed the song at Fred's bedside, dating the manuscript five days before his death.
John Wellington Wells, the title character in The Sorcerer, who actually was supposed to be the villain, but unfortunately his evil is only hinted lightly upon in the text so one feels the retribution is a bit overdone. In the end there is a choice of whether he or the handsome Tenor Alexis dies; the audience tends to opt for the tenor. It doesn't help that most people can't stand Alexis anyway.
Dick Deadeye, who is hated by his shipmates just because he's ugly and a hunchback— true, he does rat on the two lovers and is not a very nice guy, but many people still feel sorry for him. From Pirates on, Gilbert tended to redeem his villains.
Values Dissonance: Princess Ida is an attack on feminism that was considered outdated when it came out.
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