If theres nothing out there there seems to gap in the market between tools like enterprise architect (repository-based models which are very standards based (UML, BPMN etc) and inflexible and basic process drawing libraries like mxGraph .
I see an opportunity here that sits between the little-to-no documentation except user stories and code movement and the horribly inflexible and maintainable 'enterprise' models out there - but happy to hear dissenting opinions on why thats a terrible idea!