If there's ever going to be sense that my civilization is thriving, the individual settlements (could be 100+) are going to need to have some ability to take care of themselves and not need us to hold their hand every 3-5 turns. Perhaps make it possible to develop guard towers for settlements, beef up it's defences in general and make it less likely for the mobs to be a bother. Giving these guards better spell gems (I hear the devs want to make it so you can give your old items to npcs) and other items would increase their effectiveness in battle.
Also the mobs that would appear at a settlement can sometimes be of a trivial level compared to the civ level and would be easily dispatched while some mobs would then come along and really challenge the defences of a settlement. Randomize it up a bit...from what I can tell about fantasy/medievil type civilizations in games the mobs in the surrounding area aren't always threatening to engulf the entire settlement but they're still a danger to innocent defenceless citizens who might be in the wrong place at the wrong time.
As for the hostility of the world, I'm not really sure if a civilization has any place to grow if this world is as hostile as people say it is. Maybe the world is incredibly hostile, but that's why you grow as a civilization....you develop ways to take care of the problems. If you can take care of a mob of monsters then surely there should be npcs in the world who can do the same or be trained/helped to do the same. Plus you could have more mobs attacking settlements at once if you had it so you weren't expected to take them all on.
There could always be boss mobs that are very rare that even the strongest of settlements would struggle to defeat. So they might send out a desperate plea to you through the illari stones.
This is all mostly for when your civilization has gotten huge and a message comes up saying "settlement is in trouble at (-458, 788) and you're just staring at it in disbelief because it's so far away from you and you were just about to go after the overlord.