If I'm understanding your question correctly, it sounds like you're just generating cache tables for each variant of the root table with a different set of group bys (although I'm curious why you wouldn't want live views instead). I would recommend a python script that accepts a list of group by parameters. When executed, it loops through the list of parameters, generates and executes the DML with those parameters, then runs a generated query to store the results in the new table.

Feel free to message me separately if you want to dive into specifics.