I've been playing the beta only a few days now but one thing I've noticed is that the areas within your kingdom but outside of your city are dead. They're both useless and boring. The worlds been ravaged - you're fighting to survive and build a kingdom in one of the few restored areas in the world and no one is either protecting your area of influence or settling outside of your city in smaller towns?
That just seems odd to me. And I'm sure this has been mentioned before. In fact there is a thread on the first page that mentions just this. However the solution suggested there in is different from mine so I figured hell, why not make a new post?
Since it doesn't make sense that cities are completely isolated islands, why not have ambient growth within your area of influence. Small, non-player, non interactable towns and settlements which, do little more then exist. When the boarder of your city starts to knock up against them they dissolve into the city itself and you need take little or no notice of them.
Of course, this is purely cosmetic, something that makes the restored areas seem more alive without adding any real interactivity to the cities. You could make research that affects how these cities grow - perhaps they can be used to add a small boost to your population when you integrate one of them into your city or use them as a sauce of slave labor with the right research.
The other part of this idea is slightly more than cosmetic - It doesn't make sense to me that there are no watch towers or boarder patrols and I think having research that builds these along your boarder would be a good thing. I'm not talking something that stops other players or factions or higher level monsters. I simply mean small, non-player controlled, interactable or placed structures that serve as guard posts of sorts. They can be used to explain away the absence of low level monsters in your region, add a level of life to the world and perhaps with research be used to slow down the first attacking turn of anyone entering your region. Not enough to even damage an enemy unit mind you. Simply slow their movement speed for a turn.
And that's it. =P