[streetpro]

You have to define what to improve...
if Cd (coefficient of drag, basically how smoothly the car goes through the air) then take a closer look as basic shape has better Cd then M3 (and it makes perfect sense as M is optimized for performance, not consumption).
If more downforce is asked, it comes with a price tag of higher drag and additional spoilers/wings...
and yes, the basic shape has light front at high speeds (over 180 kmh let say), anyone on autobahn has experienced this phenomena when chasing a P911T I guess :-)
Vented hood improves the matters a bit, at least for me it has worked fine (the vents/louvers must be in the front section of the hood, where the low pressure area is, not at the rear where is the M3 intake opening and people have feelings that it ventilates the engine - in reality it does the opposite).