I think you need to step back and think about your primary objectives. I’m guessing the main objective is for something that “just works” for github projects.
The need for pom.xml/ivy.xml is now a custom requirement and will likely require a custom “publish” step. So, the convenience seems to have faded and it now looks like you’re rolling your own repository with it’s own publishing mechanism.
Have you considered using github as a maven repository?