I really like this idea! I feel like you could have the character mapping and input be geared towards writers for a story documentation tool as a UI and framework for the generated content would be in what a writer would need. Then offer as much or as little generator access as the user wants.

For that generated content, I do a lot of character creation in a completely different context than writing/D&D, and I would pay for a service or software that let me input or override the story type character data with ones of my own making.

The goal of self-sustaining stories that can be tweaked or woven into is awesome.