You can preset how Revit exports its objects into DWG through the use of the following:
R Button - Export - Options - Export Setups DWG/DXF.
In the window that opens, you can use preset layer conversions from the AIA/British Standards etc or you can create your own.
Be mindful that Revit is not AutoCAD, it creates content differently using intelligent objects not dumb lines. So trying to convert some of these objects into a particular layer is impossible (unless you want to do it for them in AutoCAD).
My approach to working with users who draw in AutoCAD differs and this approach is something you may need to consider as well. Firstly, you use Revit. It is your preferred software. If you need to do any post-export work, you are in effect doing the work for someone outside of your company and wasting your bosses money.
I limit my post export work to auditing, purging and zooming to extents. I leave the rest up to the consultant, who's choice to use an out-dated software is theirs alone.
Exported DWG content to be issued shall only be saved in the drawing issued folder with the DWG’s named the same way as the PDFs. (See section 16.1)
__________I'm the guy they come to when they didn't follow my recommended workflows.__________