When I first saw Pulp Fiction, I came out of the movie saying, “that was the perfect movie. . .the movie I’ve been waiting my whole life for.”
I don’t know if I’ve felt that way about a movie, since.
The Big Lebowski comes close, though.
It would probably be an action-adventure film, with well-drawn characters and lots of witty dialogue. It would take place in an expansive, believable science-fiction world. And it would incorporate elements of westerns, one of my other favorite genres.
In other words, it would be Serenity. 
I walked out of that film with the uncanny feeling that it had been designed with my tastes specifically in mind.
But they cut the full-frontal shower scene between Kaylee and Inara, and River’s shirt wasn’t even a little bit torn after the big fight, so it falls a bit short of perfection in my eyes. But otherwise I see your point. 
There have been three perfect movies so far.
Ocean’s 11
Love Actually
Shakespeare in Love
Why are they perfect? Besides the all-star casts, brilliant writing, directing, cinematography, costumes, and scoreS? They’re just incredibly watchable in the way that a great beer is incredibly drinkable. The scenes are so perfectly timed that the plot flows along effortlessy.
And boobies.
I was going to nominate The Maltese Falcon as a perfect movie (Humphrey Bogart version, natch). But in another thread somebody mentioned that Mary Astor was badly miscast as the femme fatale, and I watched it since then, and yeah, she sticks out like a sore thumb. She’s just all wrong for the role. She looks and acts like a frickin society dame stuck with the peasants, not like the sort of dame a hard-nosed PI would lick his lips over. Sigh.
ditto. I remember seeing it for the first time at the theatre with a friend and walking out and saying to him “Now THAT was totally my kind of movie.”
In the 1930s, the Shadow battles white slavers. Guest appearance by Doc Savage. The two don’t get along.
The Master of Men’s Minds! Blazing automatics! Half-naked women! Autogyros! The Man of Bronze! Margo Lane! Ham and Monk!
We need a version with Bogart as Spade and Bebe Daniels from the 1931 version as Ruth Wonderley --just like we need a version of the Spanish-language Dracula with Lugosi as Drac.
Throw in a zeppelin and this gets my vote, too.
Oh, and it could use a robot. A big, lumbering, art deco robot.
(slaps forehead) Of course, zeppelin and robot! How could I have forgotten the zeppelin and robot? Obviously too much caffeine today already.
It must include (but not be limited to): pirates, ninjas, dinosaurs, dragons, explosions, tornadoes, swordfights, bullet-time aerial-style martial arts, drugs, sex, nudity, omnisexuality, tight clothing, a kick-ass rock soundtrack, witty banter, wisecracks, quips, comebacks, one-liners, mad scientists, inept henchmen, flying spaceships, and goats.
Thus sayeth Kythereia.
Killer bees and lots of them would be nice.
Apart from that, there have already been 3 perfect movies.
A Matter of Life and Death by the Archers
All About Eve by Joseph L. Mankiewicz
Young Frankenstein by Mel Brooks
And a special runner-up prize to Casablanca
Ghostbusters meets Weekend at Bernie’s
I appreciate that, when I posted I was a bit worried that I may come off as more insulting, which I certainly didn’t intend. (Just say that, IRL, my sense of humor generates hopeless misunderstandings.) Back to the topic at hand, I’m afraid I can’t parse out parts of one movie and mentally splice them into another, or take various themes and conflate them into a whole. I suppose the one thing that draws me toward movies are the protagonists, who, in my favorites I’m noticing, usually possess at least one of three traits, those being 1) An inviolate sense of justice 2) A decidely non-conformist worldview 3) A skewed (hopefully dark) sense of humor.
In the interest of full disclosure, I too must admit that I like Armageddon. Not one of my favorites, mind you, but I’ll watch it.