John,
I really think you are over complicating this with your attempts to improve these definitions. The definitions of molds and casts were made very simply at the beginning of this thread and that’s really all you need. Molds are made from originals, casts are made from molds. It’s that simple as I see it.
I suggest that you take trace fossils out of this mold/cast realm. Trace fossils are a whole different bag of worms. It would be helpful if you would do some research on them before trying to invent new definitions. I suggest Osgood 1970, Frey 1975 and Seilacher 2007. Trace fossils fall under a large variety of morphologies. Trace fossils do not ever include imprints or molds of body fossils although those imprints and sometimes true body fossils are directly associated with the trace that the organism made. These are wonderful finds as they specifically identify the trace maker, i.e., the horseshoe crab fossil (body fossil) at the end of its own trackway (trace fossil) in Solnhofen.
I don’t think I can help you any further.
Jack