Capt. Video,
One route you forgot was mine:
1) Graduate with a degree in Drama, and after an "Oh crud!" moment realizing actors make no money, decide to get into production
2) Score your first PA job through your accountant's son, who doesn't hire you but refers you to a few production companies
3) Build that into producing TV commercials (tiny 35mm films)
Also, I just met somebody who dropped $30,000 on a first film (instead of film school) that has major problems in post because of screwups made while shooting, doesn't have the $ to finish his film, and doesn't know what an Arri SR2 is.
In the end, I think any path will do, but film school produces a more consistent product - YMMV)