Right, the Morelli shape, and the Aptera are specifically meant to provide side-by-side seating. And the earlier Aptera prototype "Zen" had a Cd of just 0.11 -- I think that will be hard to beat.
The only other car with actual wheels on the ground that has an even lower Cd is the Mercedes Bionic model, which has a Cd of 0.095:
This is the basis for my CarBŒN Concept EV Open Source Project.
The basic boxfish model had a Cd of 0.06:
It has a nearly square cross section and so the interior volume is very usable.