Immersive: Roman City Restoration mod for Total War: Attila.
1) The City Sprawl of the WRE is a partial copy of the ERE, and the walls are from RII’s campaigns. The key buildings that are unique to the WRE have been left untouched (Such as their Theatre, Military Buildings, Civic Centres), as this does add some of the “crumbling civilization” flavour, while maintaining Rome’s dignity.
2) The vanilla city sprawl of the WRE without this mod is a carbon copy of the Barbarian factions (it’s where the mud-huts come from), and did not even have any pavement/concrete/streets under their buildings – this is where the feeling of “Too much brown” came from during all my playthroughs – because you were literally looking at mounds of earth in the middle of your cities most of the time.
You are now the last bastion of Civilization, and your cities reflect that reality.