You can create team for each of the 3 brands you have so the content, playlists and schedules are under the specific brand. When that is set you can go to the Users and Teams page and switch team to manage the brand you want. In a way it's even better than having folders for playlists and schedule. You can also add users to your team in the future to help you manage the content.
For more information about how to create team please refer to this blog post. https://screen.cloud/how-to/product/users-and-teams