[sector24]

I think it depends on what nation you play as. For instance, some nations are not good at straight confrontation, like Pangaea. Other nations need time to build expensive but durable units like Niefelheim. Some nations can generate large quantities of above average troops every turn like Ulm.

You probably shouldn't be building as much PD unless you're defending a choke point or a province that is going to be attacked next turn. With all that money could be buying standing armies that can be one or two turns away from any incoming threat.