How should you organize a company intranet with Atlassian's Confluence?

I manage my company’s intranet with Confluence. There are multiple sub-companies, products, and projects. How do you suggest organizing the intranet? Is it purely hierarchical? E.g. Head Company > Sub-Company > Product > Product or flatter. Does each of those nodes get a Space? Or are they pages in a broader Space? Would love your thoughts.