I planted an Influence starbase near a minor yesterday, and got an immediate bubble of pink. Neat! But... what do they do, exactly? And why spend $500 for a 5% boost, if a $150 starbase is already 96% as effective without any modules?
More importantly, what do economy and military bases do without any modules? Just sit there?
On another note, how do you defend starbases? I planted a couple ships on a military starbase to help protect it. But when attacked, the enemy attacked the starbase directly, ignoring my "defenders" (that's OK since it was very highly upgraded, and took no damage). Since you can't put a starbase in a fleet, is there no way to protect them other than intercepting the enemy at a distance?
Also - are starbases EVER cumulative? The AI likes to build econ starbases right next to each other... to they actually benefit from that, or is it an AI error?