This air guide sends air exiting the front heat exchangers to blow over the friction ring of the front brakes. So the calipers, the center of the rotors, and the face of the rotors are getting cooling airflow!
The rear suspension is pretty close to the previous generation 991 multilink with some refinements to reduce weight.
The main difference is the upright looks slimmed down and hollowed out. It is probably much lighter than the old part. This is a pretty slick design!
Overall the layout looks to be pretty close to the 991, we would have to see the 991 side to side with the 992.