Aether is often excluded and it's association is with the center rather than the cardinal directions. While it is the inner self, I have seen emothions and feelings (along with art and beauty) more often associated with water. For example, in Jade Empire there are four Magic Styles based around the four elements except with ice replacing water, while Aether is represented by the very Chi through which these magics are used. Aether is always on a deeper level than the four material elements, so I would say that Aether fits best with the Great Mother, Herself. And possibly the Empress by extension. 

Aether/Void/Spirit/Whatever you call it is one element, but it is the only spiritual element while the other four are physical. To expand my previous thought by adding it: 

Earth = Zhuni 
Water = Xerin 
Air = Xenkorian 
Fire = Etherians 
Aether = The Zhu Empire (The whole of the Zhu Empire working in Harmony with nature and the Great Mother.)