I'm just comparing it to what has been done in the past and to illustrate how much unspun weight the suspension system could handle. Even though single axle rear suspension does not provide the handling capabilities of independent rear suspension, it still is safe to use and provides a good ride, it also used to weigh a lot too with the axle housing, differential and brake assemblies. If the motor is more sensitive to mechanical stress and damage, then the rear wheels would be the logical place for it. In an EV the motor is not the biggest center of mass, the battery is, so placing the drive wheels at the front under the engine has fewer advantages and adds complexity and expense in an EV.