The fender slotting is generally a good idea I think.
The Remmele bug also has extensive holes in the rear apron and rear fenders for letting out hot exhaust radiant heat as well as decreasing rear lift imo.
I suppose any rear roof device works, if only to distort the laminar flow there so lift is reduced.
Look at these race bugs for reference of things you can do. Racing brings out the best developments in people don't you agree?
