As somebody who hasn't played many of the civilizations, I base the Civilopedia on who to pick next. The Austrins look incredibly boring if you just look at their Civilopedia page. Their migration special project is not mentioned, nor are several other features that are unique to them (Air II allowing them to summon a pegasus [who can then be mounted], master outfitter providing with them with Windstones, etc.). I think these kinds of things, or even semi-unique things shared by only some civs (such as doubletime from Master Siege only being available to Khazad, Mechanos, Austrin, and Hippus), are worth mentioning in the strategy section of each civilization. I could make that Austrin Pedia entry if it would be helpful; though I'm terrible at actual strategy, so I wouldn't be able to go beyond just saying what is unique to them.