Eliminating the front brake is a non starter from a safety POV for a powered bike used for transport. In a threshold braking/ emergency stop situation, all of your stopping power comes from it. Coaster brake bikes have a limit of about 20% of the braking performance simply from the geometry, before getting into heat dissipation and the loss of control from skidding.
(LWB Recumbents and tandems are different, they’ll skid the front wheel before overturning)
That's quite a niche of a niche vehicle. Pretty cool, but at 70kg, and 500W, I wonder how it's legal in Europe without being registered as a motor vehicle.
(LWB Recumbents and tandems are different, they’ll skid the front wheel before overturning)