Note: I haven’t really reread the post I’m linking to. Instead, I want to make some spontaneous remarks. I think epithumia = eros, since Plato sometimes uses the terms eros, thumos and nous, and at other times uses epithumia, thumos and logos, and these evidently correspond to one another, respectively. Also, you seem to posit three different things, united in a trinity, whereas I discern two opposed/mirrored things, divided in a unity: logos is the “third” that comprehends the two.