A problem I've noticed on the harder AIs: they rarely, if ever, scrap their structures, even if it's a good idea. For instance, once I was playing with an allied hard AI who maxed out on logistics structures on his front-line planet, but hadn't built any culture centers there - so, later in the game, enemy culture was overthrowing his planet every 10 minutes or so, my ally would recolonize and upgrade, and it would happen again, etc.
I'm wondering if this might also pose an impediment to the AI building superweapons - they'll have to have at least 18 tactical slots free to build one, but (so it seems) are quite prone to filling out all available slots as soon as they can. So, they might fill their slots too rapidly to ever have enough free slots to build a superweapon.
Hmm how about an option under "game options" when your starting the game to not allow or reduce mines? the ai producing 150 mines on every one of there planets can be pretty annoying. And time consuming when your tryin to advance quickly.
Mines being annoying and time-consuming to get rid of... is kind of the entire point of having mines in the first place.
However, a change to the "build as many mines as possible everywhere!!!!!!" strategy of the AI would be appreciated.