Putting to one side, for a moment, the appalling loss of life, on both sides, of the aerial bombing campaigns, there's the question of the effectiveness of the German missiles. On Blossy's figures, the V1s caused roughly 6 deaths per sortie. That is, I would have thought, lower than the average deaths per sortie of the Allied bombing campaign. Civilian deaths were not the primary objective of the bombing campaigns, but they might work as a rough proxy for all the desired outcomes (chiefly loss of industrial capacity and damage to morale).
How do the cost calculations work? Each V1 was a total loss on its first and only mission, whereas bombing aircraft were reusable--up to maybe 30 missions. How did airframe costs compare? There is also the loss of highly trained (and very brave) aircrew--I don't know quite how you figure that in, or how you offset it against the deaths of slave labourers building the missiles.
The economics of destruction and suffering is a horrible thing to contemplate, but presumably it's worth knowing whether the missiles were in fact effective weapons. Intuitively, one would expect the costs (of all kinds) of the V2 exceeded the damage caused by a good measure, but does anyone know about the V1?