Okay, I wrote a bit about a semi-mumblecore film, True Adolescents, which I characterized as a "poor man's About a Boy".
Maybe that's the way to go. Strive to make a movie that will be a poor man's version of some better movie. But you'd have to borrow the movie's basic theme and little else.
Like True Grit. A horrible girl coaxes a murderous drunk to take revenge for her.
Star Wars. A whiney adolescent joins a reactionary political group intent on restoring a royal family to power by blowing up a large object and killing thousands of people.
Easy Rider. A pair of drug dealers can't understand why people don't like them.
Animal House. Obnoxious, underachieving college students feel persecuted by their more successful peers.
Natural Born Killers. A below-average couple becomes famous but gains nothing from it.
Shane. A guy with some history of violence moves in with a family and eventually kills people for them. (Like Slingblade.)
Gone With the Wind. A husband can't understand why his aggressive, self-centered wife is in love with a sensitive wimp who's already married.
It's a Mad Mad Mad Mad World.A mild mannered dentist tries to be reasonable, but when people respond unkindly to him, he decides to show them what kind of man they're dealing with and becomes overly aggressive.