Very extensive work there, Jeremy.
But I think you misunderstood Cablefish a bit. It wasn't about copying some historical styles. I think he meant that you should study existing examples of alien races / human cultures that portray various aspects. Like how does one convey words like "arrogant", "noble", "pragmatic" audio-visually in general. Certain shades of colors or musical styles lead to certain assumptions by the viewer. I would have tried to answer in similar way myself, maybe we got your question wrong.
I personally find the alien races you've created a bit one-dimensional and extreme. Seems like you wanted to make all of them different from humans but they don't seem so different from each other? Cold and machine-like thinking lacking the softer side altogether. On the other hand you didn't try to describe kokome in short summary of their ideals. Rather you write many chapters about how they have various kinds of x and y without extremities. Why is that?
Because I was starting to wonder if you can really make such a rule for the alien races consisting of billions of individuals? All kinds of humans exist and even small nations or counties aren't homogeneous in morale, social values and nature. Every day people fall victim to stereotypes and misconceptions so on the other hand I would like to see some sci-fi handle alien nations a bit more in-depth. Maybe that was your intention and it was just misrepresented due to the different motives in that post.
Well, good luck with your project anway. You've done lots of writing and you'll have immense amount of work ahead of you when you turn that novel into a game