First of all, thank you for the Cables Workbench. Even though I haven't had the chance to use it yet, it looks incredibly promising. A robust bridge between QElectroTech and FreeCAD is exactly what the FOSS community needs, especially for electrical control cabinet design.
Actually, the workflow could be optimized like this:
Component Mapping: Create element templates with STEP file associations (this could be handled via a central config file or metadata within the symbols).
Spatial Definition: Adding elements to the folio and defining their physical location (e.g., Rail/Row + Position) directly in QET.
Project Configuration: Using a config file (CSV/XLSX) to define cabinet dimensions, DIN rail layouts, cable duct details, and origin offsets for various STEP models.
Automated Generation: Executing a script to generate both the 3D layout of the cabinet and a 2D front-view DXF for manufacturing.
Your solution is very close to what we are looking for. While we are not experts in QET scripting, the XML-based file format seems accessible enough to figure out.
We would love to help improve your script however we can. Looking forward to seeing this progress!