Just to be clear, I have no problem with vast empires populating the map, that's Civ, mod or no. But in a dark fantasy setting, there should be tracks of wilderness within every empire's boarders that still hold dangers for the surrounding areas, be it dark forests that travelers don't return from known to be home to goblins or desolate peaks said to harbor the undead.
Sure, realistically an empire would fund parties of explorers, military ventures, and even go so far as to destroy a dark wood to ensure it's population is secure, thus in Civ your culture boarders edge out the capacity for barbarians to spawn within your boarders, but this is a genre based mod, and in that genre those things just don't happen because the adventure options for said areas of untamed wilderness are inherent to the feel of the setting. That is what I feel is missing, and that is what I would like to see preserved, if possible.
I think that the wild world should remain until the end of the game, always providing you with reasons to be on your toes, and also adding to the feel of the game and allowing for some interesting quest and event options to boot. I would like to see it be the case in a marathon or epic game just the same as I would like to see it preserved when playing on quick.