Poly Draw Retopology System

Along with the new sculpting capabilities of Blender 2.81, I think it would be fantastic if we had a dedicated Poly Draw or Retopology system. I've seen some videos revolving around retopology, but they involve selecting edges, pressing E to extrude, moving the edge, and then selecting the individual vertices to move them around.

In a dedicated mode, we could have the left mouse click specifically draw out more polygons or edges, and have it conform to a selected mesh, similar to the current method. Using different combinations of Ctrl, Alt, and Shift, we could drag out edges, drag out entire polygons from corners, and position vertices and edge loops as needed.