Isn't the AI building too much starbases?
Or building them too early?
Well, after a few games with Entrenchement, i noticed the AI seem to build starbases way too early in the game, and tend to have quite a few all over the place. The problem is it build them before having a good fleet, and sink way too much resources in them while not having the economy to upgrade them properly. In my current game i destroyed at least 3 starbases from a hard Vasari AI that has only 5-6 planets... Once the starbase is gone, it has very little fleet to oppose my fleet.