Revit Elevations are great, quick and automatically generated. Then you hear the shouting start. In AutoCad I use layers to distinguish between objects further and closer, by assigning colours.
So the quick Revit answer was ...use your linework tool.
Then another solution was draw in glass walls, cutting through your project, then hide these, then, then, then. So this seems a bit of a way around.
I tried playing around with Override Graphics in View (By Element)
Go to your elevation select the objects ( in this case walls). select objects set back, Override Graphics in View (By Element) you can go for the quick option of halftone here, or change your projection line weight thickness, you may even want to use shades of grey.
Similarly, you could then beef up the line weight of objects closer, also by Override Graphics in View (By Element) and change your projection line weight thickness.