There aren't really any what-ifs because none of the actors were known; Gunnar Hansen regarded Leatherface as having an intellectual disability and performed him that way, and John Larrakat (as transcribed) narrated the opening credits, was paid in marijuana and, per an interview, had not seen the movie as of about 2008.
Gary Oldman as Oswald; Seinfeld spoof; Pesci-Tommy Lee Jones wig battle; Kevin Bacon's career revival; Oliver Stone's Dave cameo; Tommy Lee Jones in gold paint; Dealey Plaza recreation; John Williams score; New Orleans setting; specter of JFK; character actors in tiny roles
Offered as number one: Oldman as Oswald is creepy, great, and looks like Oswald.
Oldman must have shot much of his material separately with Stone; a 'Gary Oldman cut' as a standalone Oswald movie is wished for. — Chris Ryan
Deleted-scene story: Oldman asked Stone to point the camera at him late at night for an elegiac Oswald monologue; Stone shot him in a casket and planned to end the film with it before making a different call; it can be found on YouTube. — Brian Koppelman
The 1992 Seinfeld spoof 'The Boyfriend' features Wayne Knight and Keith Hernandez; Hernandez is praised and then jabbed as possibly a QAnon guy.
'The Boyfriend' is remembered as the episode that showed Seinfeld would be the biggest show, with the spitter bit called lights out. — Bill Simmons
Bacon is said to call the film a turning point that reignited his career, leading to A Few Good Men. — Bill Simmons
Stone's self-deprecating cameo in Dave two years later has aged best for one participant. — Bill Simmons
Tommy Lee in gold paint getting slapped by Pesci in a Dangerous Liaisons outfit is praised as the good version of a wild idea, unlike a cut Nicholson idea in The Departed; Tommy Lee doing it is what makes it great. — Bill Simmons
Objection: the same scene bumps against what's aged worst, the film's attitude about homosexuality, called retrograde and unacceptable; the counterpoint is that it was part of Garrison's case against Shaw and that era's judgment. — Brian Koppelman
Stone recreated the assassination in Dealey Plaza, spending $4 million to restore it to 1963 conditions and reroute traffic; Sutherland and Costner memorized their monologues. — Bill Simmons
Debate on whether acting is mostly memory: one participant says no, the camera reveals compelling people like Sutherland and memorizing matters more in theater; it is jokingly settled at 70% memory. — Brian Koppelman
John Williams's score and New Orleans as a setting are named.
The specter of JFK himself: the speech that opens Stone's documentary, the Caesar-like shot in the X speech and the still photograph of Kennedy.