While I realize that XMI is not applicable to the majority of model types that are provided through GoJS, it does allows for interoperability of UML/SysML/BPMN models among platforms.
Specifically for BPMN models, I have a repository of several thousand models that I would like to import into, as well as export out of GoJS.
Is there any chance that you will support a request for porting models from/to XMI?