We try to make cars more aerodynamic, but race cars regularly sacrifice CD for downforce and other concerns that are not ours. Honestly, I do not know what good either of those spoilers would do, but I found a picture of the front of that second Civic, The World's Fastest Civic:
They fastened those bands across the roof?
Have you ever used the aerodynamic template tool for your car? My spoiler is a couple of inches high, but still several inches under the template, so it probably does not affect airflow at all. If you made a rear wing that extended past your bumper, you should be able to reattach airflow. Good luck!
There have been some discussions of the double spoilers of the Merkur Xr4ti, but that still does not approach the template.
