I'm always having trouble finding the right options and hooks to modify the Related Products section in WooCommerce. PBF adds the default columns to 3, but WooCommerce defaults the products per page to 4. It would be nice to have an easy place to update the Related Products Columns much like the Related Posts section in posts. I thought maybe enabling Product Settings (via Theme Settings) and modifying the Related Posts section would update Related Products but, no dice. Maybe if WooCommece is installed, the Product post type via Theme Settings should be enabled automatically, and the Related Posts section could better relate to Related Products.