Undergorund of the Buildings and Multilayers

At the moment, when I want to build a sewer or cellar system beneath a village, I first build the village, export it, and then import it again to use as a reference for where things like toilets are located. I then build the sewer system and dungeon accordingly.

Having a directly implemented system for this would be extremely helpful. Multiple layers for a map that can be easily edited and exported independently would make the process much more streamlined.