For companies with a large number of individual projects, such as contractors, it's desirable to organize the projects in a folder structure to prevent the project list from growing out of control and make finding projects easier.

If you could create folders at the highest level simply for display purposes (I wouldn't even consider namespacing the projects a requirement), it'd be a huge help. The natural structure I'd setup would be Customer (Folder) > Customer Site (Folder) > Project > Repos.

Additionally, permissions at a folder level could allow clients to be given access in source control to their site as needed without needing to control the individual projects.