PS HCM - Security User Profile - Minimum Roles To Start User

I am beginning to redo all security to take advantage of Fluid, and so I was going to take a current user profile, wipe out all existing roles, and then add the essential roles to get a basic user. From there, I was going to make the Fluid Roles Dynamic and assign automatically.

All the people I have been looking at in DEMO have their work roles, but I need to just have the essentials to create a start template.

Can someone tell me what the required Roles delivered from PS are necessary to stat a user?

David L