Do AI factions build new buildings and upgrade them when they get new colonies via invasion/donation?
Because when I check colony info, I often see that they they don't build industries and not upgrade them.
They do, but I'm not quite sure how the logic works.
If I found a new colony and donate it so I can purchase back the governorship, the AI will always start to build mining/farming immediately.
I've definitely seen them build orbital stations, patrol HQs, and even upgrade heavy industry to orbital works. A colony growing in size triggers it considering building things. Otherwise, it seems to happen infrequently/rarely? Whether and what they actually build may depend upon the overall economy of the faction?
One thing I have noticed is that giving them a market that doesn't have any resources seems to confuse the AI and they won't build anything until it grows.
Speaking of purchasing governorships, I'm sometimes annoyed at the lack of an option to become governor after invading a planet. I either have to hand it over to my faction completely--and am frequently unable to purchase governorship because of the size--or found my own faction. I was thinking it would be nice if there was a third option to purchase the governorship, unrestricted by market size, with a few caveats: 1) larger markets should require cooperative standing and 2) the cost should be something like (200-250k * market size * number of markets controlled by the player already). It would seem to make sense to me that factions would be keen to help the rising hero advance their own interests, but would grow increasingly jealous/nervous if the player consolidates too much power within their organization.
That said, I didn't look into what happens when the player is hostile to independents, and vultures fighting people on their own is undesirable.
It happens constantly. They also attack my convoys and orbital stations. There were 5 markets in the system. Initially only 1 was Pather. I have conquered 3 of them for the Pathers. The final one is a normal faction that isn't currently hostile to the Luddic Path, and it is continuing to churn out vulture fleets at a prodigious rate. The trouble is that the vulture fleets fight the Pather armadas, which produces salvage and derelicts, which spawns more vulture fleets, and on and on it goes. It's like the independents have a high command in the system despite having no markets.
I purchased the governorship of one of the markets, so there are now 2 Pather High Commands in the system. It's gotten to the point that the Vulture fleets are destroyed almost immediately, and two of them are spawning every day after I've been in the system for a little while.
Maybe if a system is controlled by a pirate faction, vultures should decide that it's too dangerous and steer clear. Another option would be to just give a limit of 2-3 fleets and then add a cooldown of at least a month before more spawn. After all, they are presumably economic opportunists, not soldiers prepared to die for a cause.
I would also second that it would be nice if there were settings to disable or adjust this feature.