Allow more than Project Lead or Unassigned Roles as Default Assignee for Projects

As a very large enterprise, we have many Projects with many people working on them.  Often the Project Lead is not a technical person and should not be the Default Assignee for a Project.  I would like the ability to be able to choose another Role on the Project as the Default Assignee.  For example, I would like the ability to create a role called Default Assignee2 (or whatever I decided to use for that particular role) and select that role as the Default Assignee from the Edit Defaults drop down in a Project. 

Another option would be to be able to select a specific team member by name on the Project as the Default Assignee, i.e., anyone that displays on the Users and roles page for a Project.

I realize that there is a work-around to this issue by creating a Post Function in the Project workflow using the issue.get("project").key in functionality.  However, this does not allow the Project Lead to set the Default Assignee for a Project.

Oftentimes in our Projects teams have different team members responsible for that role on a weekly basis.  For example, for the first week of the month the Default Assignee would be John Agile, the second week of the month the Default Assignee would be Dave Jira, the third week of the month the Default Assignee would be Samantha Manifesto, etc., etc.  Having this functionality would allow Project Leads for Projects to assign the Default Assignee to team members of the Project as needed.