His accomplishments at Marvel were actually pretty impressive. He went on to do other interesting things throughout our period. Here's the Wikipedia article:
Jim Shooter may not have been Darth Vader after all
From the article - regarding his Marvel tenure:
"With the quick turnover at the top, Shooter rapidly found himself rising in the ranks, and in 1978 he succeeded Archie Goodwin to become Marvel's ninth editor-in-chief. During this period, publisher Stan Lee relocated to Los Angeles to better oversee Marvel's animation, television and film projects, leaving Shooter largely in charge of the creative decision-making at Marvel's New York City headquarters. Although there were complaints among some that Shooter imposed a dictatorial style on the "Bullpen", he cured many of the procedural ills at Marvel, successfully managed to keep the line of books on schedule (ending the widespread practice of missed deadlines), add new titles, and develop new talent. Marvel enjoyed some of its best successes during Shooter's nine-year tenure as Editor-in-Chief, such as Chris Claremont and John Byrne's run on the Uncanny X-Men, Byrne's work on the Fantastic Four, Frank Miller's series of Daredevil stories, Walt Simonson's crafting of Norse mythology with the Marvel Universe in Thor, and Roger Stern's runs on both the Avengers and The Amazing Spider-Man.
"In 1981, Shooter brought Marvel into the lucrative comic book specialty shop market with Dazzler #1. Featuring a disco-themed heroine with ties to the X-Men (based upon an unproduced motion picture set to star Bo Derek), the first issue of this series was sold only through specialty stores, bypassing the then-standard newsstand/spin rack distribution route altogether, as a recognition by Marvel of the growing comics shop sector. Subsequent issues of Dazzler, however, were sold through newsstand [returnable] accounts as well. Dazzler was the first direct sales-only ongoing series from a major publisher; other Marvel titles, such as Marvel Fanfare and Ka-Zar, soon followed. Later that same year, Shooter wrote Marvel Treasury Edition No. 28 which featured the second Superman and Spider-Man intercompany crossover. Additionally in 1981, Shooter was recognized as one of six "New Yorkers of the Year" by the New York chapter of the JayCees, for his "contributions toward revitalizing the comics industry and helping Marvel Comics achieve a new pinnacle of success." Shooter also institutionalized creator royalties, starting the Epic imprint for creator-owned material in 1982; introduced company-wide crossover events, with Marvel Super Hero Contest of Champions and Secret Wars; and launched a new, albeit ultimately unsuccessful, line named New Universe, to commemorate Marvel's 25th anniversary, in 1986.
"Despite his success in revitalizing Marvel, Shooter angered and alienated a number of long-time Marvel creators by insisting on strong editorial control and strict adherence to deadlines. Although he instituted an art-return program, and implemented a policy giving creators royalties when their books passed certain sales benchmarks or when characters they worked on were licensed as toys, Shooter occasionally found himself in well-publicized conflicts with some writers and artists. Creators such as Steve Gerber, Marv Wolfman, Gene Colan, John Byrne, and Doug Moench left to work for DC or other companies. Roy Thomas, who left Marvel following a contract dispute with Shooter, reflected in 2005 on Shooter's editorial policies:
"When Jim Shooter took over, for better or worse he decided to rein things in – he wanted stories told the way he wanted them told. It's not a matter of whether Jim Shooter was right or wrong; it's a matter of a different approach. He was editor-in-chief and had a right to impose what he wanted to. I thought it was kind of dumb, but I don't think Jim was dumb. I think the approach was wrong, and I don't think it really helped anything.
"Shooter was fired from Marvel in 1987."