Thanks for the detailed article.
It’s smart to use a package manager instead of building yet another one. I looked at Conan(https://conan.io) and vcpckg(https://github.com/Microsoft/vcpkg), but I guess they are C++ specific.
For clarification, of that last point. I was thinking of a tool/script that takes a repository/package and builds a workspace around it. Basically, create a workspace folder with a src subfolder and move the package into the src folder. That way ament can run shortly after cloning a repository/package in an arbitrary location. It takes some time to understand the workspace structure and to know how to convert arbitrary packages into runnable nodes.