For subject areas 'PPM - Project Costs' it would be helpful to add in Top Task Name as a optional feature. Since business drives into the task hierarchy, it will be useful for us to cross validate data. Furthermore, if Supplier Name can be changed from a mandatory to an optional field for 'Procurement - Spend' it will render all retrospective values.
Since the Data Validation Module is more a snapshot or point of time collection of data, I'm not sure why the system administrator cannot have more of a editable approach to pick and choose what fields should be optional or not within the detailed validation portion area.