"The easiest (and I think most successful) stories I've written or worked on were the ones that directly evolved out of the characters’ personalities, rather than just taking the characters and plugging them into a plot or situation.
Stimpy's Invention was originally pitched as a typical “Character A makes crazy inventions that backfire on character B. Hilarity ensues”
It was rejected on that basis and I reexamined it and thought that it needed something that took advantage of Ren and Stimpy;s personalities.
Ren is a psychotic highly strung nervous wreck and Stimpy is a trusting, dumb but empathetic guy who loves Ren despite Ren’s meanness.
When Stimpy realizes that his inventions are driving Ren nuts, he dosn't blame his screwy inventions, he instead thinks Ren just needs a cure for his unhappiness. Inspired with a new mission, he decides to invent something to make Ren happy. He gets the idea for a Happy Helmet.
Once we came up with that, the story wrote itself. (Well Bob Camp and I did, but it came much easier once it wasn't about wacky inventions) Now the gags were all about the characters, not about the props."