[Q]

I agree that SE IV is a very rich and therefore complicated game and therefore a good AI will be difficult to programm. But from the business aspect a good AI will be a good sales argument for a game. And if you analyse the major mistakes the AI makes you could improve it considerably.
Just one example: in the decision making of the AI one point seems IMO always to be crucially underated: the distance! The AI sends colonizers half way across the quadrant while a colonizable planet is one move away. Probably because the planet value and atmosphere type has absolute priority. The same for attack locations: undefended enemy colonies are in reach but the AI sends the entire fleet on a mission to the opppsite edge of the empire for reasons I can only speculate.
Make all these decision processes of the AI moddable and MM can leave most of the work to us! But that's probably for SE V.