Buffalkill: And how do propose to increase retention?
The most straight forward thing to me is make war happen more often. What's the two things that most often stand in people's way for starting a war? The huge potential damage and that currently if you are smaller it's much harder to fill the military gap with tactics and strategy. For the huge potential damage, look into changing how looting affects a region would go a long ways. Then for overcoming the gap because you are smaller, would be introducing more things to differentiate armies. Both of those issues are being addressed already.
As well you want to know what helps retention, making sure that new players can always be involved in war at the beginning. How? War Islands, an island in constant warfare. The War Islands is great for the game in many other ways as well, but that is the one relevant to the topic at hand.
