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.
Awesome Moment: When Wentworth saves a union leader from assassination, Scanlan (then a lieutenant at Manhattan South) steals her collar and then files a complaint against her when she protests. Barney is unable to convince him to give her proper credit, but Harris makes Wentworth's actions the focus of his column in his department newsletter... which, as it directly contradicts the official version, would cause quite a few questions downtown. Scanlan is forced to back down after Harris reads it out for the squad and Barney refuses to censor it.
Fair for Its Day: Among the recurring characters were a local gay couple, Marty and Darryl. While Marty (introduced first) was portrayed with the usual Camp Gay stereotypes of the era, when Darryl was later added the Camp was barely present. Barney always treated them with dignity and occasionally made a point of calling Wojo out on his homophobia. Uniformed officer Zatelli wasn't camp at all, and was only revealed to be a closeted homosexual after he'd already been a recurring character for some time; later episodes dealt with his fear of the effect being outed would have on his career, and his later coming out himself in support of other gays on the force.
Genius Bonus: One episode featured a tall, balding curly headed, eccentric man who wore a long striped scarf and claimed to be a time traveller. Typical American viewers would probably not have noticed at the time, but those in the know would have saw a resemblance to the fourth (then current) incarnation of Doctor Who.
Harsher in Hindsight: The second season's opening features a view of the New York skyline with the World Trade Center prominently featured. The first episode of that season is entitled "Doomsday" and centers around a suicide bomber attempting to destroy the 12th Pencinct. Not harsh enough? The aforementioned episode aired on September 11, 1975.
Hilarious in Hindsight: In one episode, a crime victim tells Fish that he looks like Boris Karloff. (Fish: That's because we're both dead.) In 1986, Abe Vigoda would star in a Broadway production of Arsenic and Old Lace as Jonathan Brewster, a part originally played by Karloff. The line "He said I looked like Boris Karloff" had been kept in The Movie when Raymond Massey played Jonathan.
In the second episode, a bomber is on the loose and Barney is looking through records. One suspect is Sheldon Hoffsteder.
The Scrappy: Levitt. Ron Cary was a good comedy actor, but Levitt's sycophantic comments and shamelessly passive-aggressive behavior towards Barney, and acting like It's All About Me while there was an obvious situation (even crisis) that Barney had to interrupt him for, made him very grating on some viewers.
Values Dissonance: The rape episode. Although the female DA treats the case seriously and laments that there will be other opportunities to test it in court, it's presented as a comedy storyline and the man is treated not so much as abusive (although he willingly admits that he forced his wife) but as someone who needs to learn how to have a candlelit dinner, and his wife as someone who should probably put out more.
The second season episode "Heat Wave" combined the two for extra helpings of dissonance. The A-plot involves Wojo almost being raped while disguised as a woman to catch muggers, and Detective Wentworth being offended that the would-be rapist didn't pick her. The B-plot involves a battered wife with a huge, ghastly bruise over most of her face deciding whether to press charges against her husband. Lots of laughs (from a live audience, not a laugh track) all around, and the applause she got for deciding not to sign the complaint ("He once made love to me in a field of daisies!") was much bigger and more enthusiastic than the applause she got for coming back a couple of minutes later and signing it.
Values Resonance: "The Harris Incident." Black detective Harris is shot at by white cops while he's trying to make an arrest. This still happens today, often with tragic results.
The Woobie: Levitt can be one. Even if he's sometimes obnoxious, he longs for respect (and a promotion) and is constantly denied it. Also, Wojo, despite his intimidating appearance, has a child-like need for reassurance that turns him into a Woobie quite often.