It would be fantastic if you could house overarching information to a group and assign people who need visibility on a group/project to the entire group—not just an item/subitem. We typically use groups as projects, items as overarching tasks (ie. Design, Copy, Render, etc…), and subitems as specific tasks pertaining to the line item they are apart of.
Project managers should be able to view groups of projects, not just specific tasks as they are managing the entirety of the project.