Another thing occurred to me that I need to think about in playing Izana. In her canon, everyone seems Japanese. They all have Japanese names and while there are some differences in facial features that might be different ethnicities, there is only one, maybe two people who might be European in features. I honestly am so new to manga, that I don't trust myself to see when they draw a person with Western features. I think I will just go with a handwaved mix of modern Japanese ethnic groups
and not worry about Europeans and other Westerners. There were 499 other space ships that left Earth when the Sidonia did after all.
And the whole reason I am thinking about this is because of the folks she will likely meet in Milliways; meeting someone white when their culture hasn't had any contact with any others is going to stand out.