Might it be best to "go back" to a conventional low nose circa 1991 since the center section of the FIA wing spec is designed to produce no DF? With a low nose all the bad suspension geometry of Zero Keel, the job of splitting the air to the R&L of the driver making things like McLaren's "shovel" necessary, better vision, better aero up the front center section of the car, maybe even a bit of added creature comfort for the drivers who would be reclining less, lower CG and more liberty for steering arms to be aligned with the upper A-arms etc. Even if the cars had to have 1mm clearance "above" the FIA spec'd center section and the bottom of the nose, it could still be designed as if it were fully integrated into the nose section like an IRL car.
I wonder if it also might help handle the side wake caused by the front wheels because you split the air once rather than trying to "reassemble" the air just after the front wheels under the drivers calfs before splitting it R&L towards the sidepods.
Has anyone posted on this topic elsewhere?