DVD Commentary: A particularly fine one from director/Riker Jonathan Frakes and Marina Sirtis (Troi). Their banter is a joy, and it's pleasing to hear them bring up all the points that critical fans often raise ('so why are the Baku all white and blonde,?' '...They're of Swedish descent'; Marina noting that her character has 'a profound grasp of the obvious' etc).
Averted; Paramount sent an astute-sounding letter pointing out the holes in the plot, including that a fight between 600 Ba'ku and the Son'a felt more like a gang war than an interstellar conflict, even (accidentally?) offering a valid rationale for Picard's interference — namely, that the Ba'ku lack the numbers to procreate and thrive in a normal environment, and hence cannot be relocated without dooming them to extinction. Piller and Berman must not have gotten that memo.
Berman played it straight, though, as he demanded that a scene where Picard expresses his sympathies to Worf about Jadzia's death be removed, even though Worf was still suffering through it on DS9 at the time. Justifiable, since it would have spoiled Jadzia's death for viewers in countries (read: every country bar the USA and Canada) where DS9 hadn't yet gotten that far along in its run.
Old Shame: Marina Sirtis isn't fond of Insurrection, saying she fell asleep at Insurrection's premiere and even arguing that Star Trek: Nemesis was better by comparison.
Recycled Set: As with First Contact, most of the Enterprise-E's sets (and the scout ship's cockpit) are actually modified versions of sets from Star Trek: Voyager The Enterprise-E shuttle's cockpit is also a redress of DS9's runabout cockpit.
Rick Bermen ordered a major action beat featuring a cave fight to be deleted, after seeing a trailer for 1997's Titantic. Realizing that Insurrection didn't have anywhere near the budget to do (comparable) justice to the water effects involved in said cave fight, Bermen wanted to avoid a comparison that would have audiences judging the film to be cheap.
Vindicated by Cable: Inverted. Insurrection opened positively, with many critics saying it broke the "odd numbered rule". However, since then, more analysis of the film has found it to be more forgettable and is now seen as one of the worst films. SF Debris summed up the film pretty well:
It isn't loved like Two, popular like Four, prescient like Six, exciting like Eight. It doesn't have people rushing to defend it, saying it's cerebral like One, significant like Three, ambitious like Five, landmark like Seven, or theatrical like Ten. Insurrection stands alone: bad enough to be hated, but not bad enough to be loved.
The film was originally a Whole Plot Reference of Apocalypse Now, with Picard in the Willard role hunting down an old friend of his while Starfleet becomes akin to the American government during the Vietnam war, providing more of a justification for Picard's insurrection. As seen below, this basic concept was tried in a variety of configurations before settling on the final product.
There were some serious rumblings that fan-favorite Q would appear. That ultimately did not pan out and Jonathan Frakes is on record as being disappointed with that.
According to Michael Piller's unpublished book, Fade In, the first draft was about Picard hunting down his old friend from the academy, Duffy, who has gone native and allied with the Baku against the Romulans. The effect of the Fountain of Youth is amplified as the Enterprise closes in on Duffy, essentially de-aging Patrick Stewart back to Season One Picard. It eventually ended with a Mr. Smith Goes to Washington like speech by Picard in front of the Federation council as the crew are about to be arrested, but stopped by a Slow Clap started by Boothby. Sound familiar?
The chase sequences with Duffy made it into the film, with Duffy replaced by Data. This explains the incongruity of Data being invited on the planet at all, to say nothing of going berserk and buzzing around Ru'afo's ship for no reason.
Quark was originally supposed to have a cameo appearance that ended up getting cut from the film.
Speaking of Star Trek: Deep Space Nine, this film was produced while the Dominion War arc was playing out on that show, with many observers noting that the flagship of the fleet really should have been on the front somewhere, fighting in this pan-Galactic conflict which involved all of the galaxy's great powers. However, neither Rick Berman nor Michael Piller were fans of the Dominion War storyline, segregating the details of that conflict to Red Skies Crossover status within the finished film.
The originally-filmed ending for the film had Ru'afo escaping from the collector in an escape pod, which then fell into the planet's rings, exposing him to such a massive dose of the metaphasic radiation that he rapidly grew younger, with the implication that he eventually de-aged out of existence. The producers felt that the ending was too ambiguous, however, and wanted a more traditional demise for him, and so refilmed the ending to have Ru'afo blown up with the collector.