All this says to me is they were looking for targets that weren't already destroyed in one of the previous bombings.
Wrong - you ignored that the target committee explicitly required that it be an urban area large enough to measure the full impact of the blast. They were literally using homes and human lives as a technology testing ground.
You also ignored that they required those targets be set aside until the bombs were ready. If they were so strategically significant, then why order they not be touched for three months? Were they just letting them kill American servicemen for three months.... or were those cities basically insignificant?
Nagasaki was one of Japan's last operation ports, why would they bomb one that had already been destroyed?
If it was one of Japan's last operation ports, then why order it not to be touched for three months until the bomb was ready?
It was literally an experiment and a message to the USSR.