I like what you wrote, but why give short story writing a ‘practical’ motivation? Why rationalize it? It’s quick, it’s like a photograph when compared to a movie, it can be expanded or serialized. All these are true, but in my opinion writing short stories, like creating anything, is an act in and of itself. It has value because it has value, and it has its masters, Carver being one of them. Most serious writers write short stories. Have you read Stuart Nadler’s The Book of Life? Or The Invisibles by Hugh Sheehy? Great collections of short stories!