There is a lot of users comments about that fabrication shape broke they regular workflow - structural family with user modification not compatible structural connections.
So my suggestion - we need more then fine detail level. It level will be for fabrication shape and hi detailed connections.
According to LEVEL OF DEVELOPMENT(LOD) SPECIFICATION PART I & COMMENTARY of American Institute of Architects
We have next parity
Revit Conceptual form = AIA 100
Revit Course = AIA 200
Revit Medium = AIA 300
Revit Fine = AIA 350
Fabrication shape of structural framings and plates with processing have more parity to AIA 400
So we may have family based geometry of structural framing/column and conceptual plates/anchors/bolts at LOD 300 and generic fabrication shape, detailed plates/anchors/bolts at LOD400 in same model.
It will be closer to the current BIM concept.
In this way we can combine custom user families with a steel workshop model in one project.
There is also a cross idea Great detail level settings to match LOD standards