It will be cool when Infiniti borrows some styling queues from the Renault Laguna Coupé below to have a fresh new look. That look would blend well with the Red Bull Racing Team and advanced styling from the FX45 series.
It seems BMW and Honda (e.g., Accord C pillar) ran Howard K. "Dutch" Darren's 1953 Kaiser Manhattan "Darren Dip" (arrow A) and C pillar design (arrow B) into the ground a long time ago.. Enough 1953 retro body lines - already.
If they're looking for some retro styling queues from a past designer like Elwood Engle on a sleek body with clean C pillar lines, here's an idea below. The design worked well for FoMoCo in the 60s with unibody (no B pillar) hardtop as the door weight can be positioned around the A and C pillar locations. If a B pillar is retained for structural integrity, it can be smaller since it will not need to support rear door weight. Modern electronics can keep the car from moving if the rear door is open while attempting to drive.