Great work, I also like the core/non-core distinction. By the way moveit_core is listed as non-core.
This is very true. It’s too bad if they removed stacks because of circular dependencies. It is like abandoning object-oriented programming because someone could not write classes with high cohesion and low coupling. In the 70 years of software engineering, this is not the first time someone has encountered circular dependencies.
Since ROS2 lacks such a level above packages, large projects like Autoware struggle to share and distribute their collections. Many important projects stay away from rosdistro, either for technical or managerial challenges, exemplified in the links above. A better discovery and dependency system would be directly based on repos, eliminating the middleman.