The organisational overhead (copy to layer, delete to layer) I think is problematic. You always have to be aware of this temporary data, names of the layer(s), etc. And now let it be not one "referenced" file, let it be ten.
I know this is not the standard CAD usage workflow. I try to evaluate QCAD to do some GIS specific tasks. I very like the mature construction possibilities of QCAD compared to e.g. QGIS. So If I want to create a development plan I need a cadastre file (or more) and e.g. an aerial view. So the local plan would be constructed using points and lines from the cadastre, snap there, and use some overview information from the aerial view.
IMHO the workflow you suggested may work for smaller datasets or maybe one file. But is complicated to teach it to not so advanced users.