Bob, you might also want to take into account that logos goes back to an Indoeuropean root "leg-," which has to do with selection, with picking and choosing. Indoeuropean was probably an early trade language, and the words that had to do with trading or exchanging were the most important. The root of logos may have meant something like a "deal." In earliest Greek, logos may have referred to "the way things are laid out" on the table for final exchange. Heraclitus (6th cent. BC) used logos to designate the universal "deal" -- the exchange of fire for everything else, its kindling and extinguishing, the incessant process that constitutes reality, a never-ending system of change and exchange. So for him logos was a principle, a rationale, a complete system. But it was also his system, his "word."
In later Greek, logos (in the sense of "dictum") becomes more and more specialized in the two directions that Nickel outlines, including the spoken word, or dictate. And it never lost the meaning of "rationale," or "reason," as well. This latter meaning it preserves in Greek even today.
Hope this is food for thought. Good luck -- Bill