I miss being able to archive projects in Workspace which I know I won't be needing in the foreseeable future, but might need again later on. Sometimes projects are complex and time consuming to create, so archiving them for possible later use would be helpful.
Also, as projects grow, tags and title are not enough to keep them organized. Folders in my view would be a great solution to this problem. For example: Marketing projects, Performance projects, Development projects. These are arbitrary names which of course I'd be able to set myself, but give them here to illustrate possible uses for folders.