We’ve finished rewriting the Military Defense AI. This work covered several areas important to making the AI nations tougher opponents. Nations will use their Sphere of Interests combined with the AI Character property Militarism Policy to influence the core the defensive decisions.
The AI work is currently focussed on border security, coastal sea zone defense and amphibious assaults. There are improvements to the sea invasion targeting. The AI should be applying more rational criteria when ordering an amphibious assault.