I think the mods would be going in the wrong direction with more settlements. That means less fieldbattles and the Hordes will be weakened severely. What if the Sarmatians, Butgundians and Goths all start with 4 cities. How many chances are there that we would see those and the two starting Hordes on the map? The Hordes would simply be swallowed up by more cities. And with no Hordes we will see a marked decline in the push-effect on the two Roman empires.