This would be extremely helpful as right now if you want to reconstruct, you would have to delete it all block by block, then add it all block by block someplace else. I suggest the ability to take a blueprint of a layout already built. Then upon placement the size of the blueprint is shown as a construction site with a terminal at the front. Reason for the terminal is to let you add the resources later if you don't have them on you at that time, as you can only hold so much in your inventory.
When making the blueprint you can have a blueprint tool that scans the area you select, where the selected area being about where you stand, or at the tip of the tool.
Could also make it so you select each block you want in a blueprint manually, though it will take longer.