Also, I am totally confused by the Special Forces section. The description of the behavior in SF classic seems to be a confused muddle of threat, threatfleet and the actual special forces.
Originally in Classic, the special forces guard posts were a source of constant trickling threat that moved around in trails throughout the galaxy. That later changed in Classic so that they would “stack up” next to player wormholes and only rush through when they had enough forces to do so. That led to a certain amount of threat hanging out in the galaxy in general, which was kinda-sorta interesting, but still not the best for a variety of reasons. So...
Special Forces
are not threat. They are a roaming
defense force. They don't ever deliberately enter a human system. They wander around between SF Guard Posts, trying to stay a couple hops out from human territory, and rush to defend AI planets that come under human assault (and they never wait at wormholes). They act as a coherent fleet in AIW1; the entire SF will get a move order to a particular SF guard post or to go defend a particular AI planet. They do not ever become threat on their own, although SF alarms, SF rally guardians, the Hunter plot, and CPAs can cause them to become aggressive. They're an important contributor to the 'guerilla war' feel, because you can strike while they're elsewhere and leave before they show up.
Threat ships, by contrast, do not appear as a constant trickle unless you have the Preemption plot on. Threat ships do hang out near human territory (though not right on the wormhole any more), but if you finish off all ships in waves and all defenders that you wake up, you don't normally see threat. Except during CPAs, obviously, but that's not a constant trickle. Since CPAs deploy in carriers they don't trickle in either, and usually they're not intimidated enough by human defenses to stack up. Threat ships offer a sort of 'how far can I push things' mechanic; you can pop command stations without clearing systems, but that frees up defenders as threat. With adequate defenses, they won't actually attack and you can clean them up later... unless a wave hits, in which case they'll frequently pile in on top of the wave, which might then overwhelm your defenses.
Threat ships also switch to threatfleet after 30 mins, which tries to aggregate all threatfleet ships into a single fleet. That fleet then hangs out a few hops away from human territory until it sees an attack opening. So there's also a time limit on clearing out loose threat before it will become much more annoying to deal with.
So, there's a couple of things lumped together here.
One is the idea of 'things which act as globally coordinated fleets', versus 'things which use only local coordination'. In AIW1, both the SF and threatfleet act as single globally-coordinated fleets. Threat ships use only local coordination. Human-friendly roaming enclaves act as a single fleet, and dark spire ships will periodically group themselves up into strike forces lead by a command ship, thus acting as multiple small coherent fleets.
Strike carriers seem partially like an attempt to create multiple coherent fleets. I think you could just take the existing SF logic and extend it to support more than a single globally-coordinated fleet of a given type and get the same effect, if you wanted the SF to be split into multiple fleets. I'm not sure that's actually a good change, though; a single SF fleet is easier to keep track of and work around but also much more dangerous.
Another is 'how do you keep a group of ships that's supposed to be a coherent fleet together'. The SF tends to spread out as it moves around because fighters are faster than missile frigates. But, that's solved on the human side by the ability to issue group-moves, so you can solve it on the AI side the exact same way. Just tell the entire SF to move at the same speed, and to switch to full-speed FRD mode when it encounters human forces. Or, if you really want to package them, just have them group up to one spot and build a 'transport shell' around themselves that disappears when they deploy.
Finally, there's a distinction between 'forces the AI uses for defense' and 'forces the AI uses for attack; the SF and threatfleet both act as coordinated fleets, but the SF only defends and threatfleet only attacks.
One more thing: AIWC's AI-friendly Roaming Enclaves and Neinzul Preservation Wardens work very much like how Strike Carriers are described. They fly around accumulating ships, and dump those ships when they encounter human forces. They're a bit different:
* They deliberately attack human planets, rather than only patrolling AI space
* They don't bother picking their deployed ships back up (because they deploy younglings that self-attrition)
* They accumulate ships to spawn as they fly around, rather than having a fixed payload
However, the Roaming Enclaves minor faction also spawns human-friendly Enclaves, which are far more effective than the AI-friendly roaming enclaves, because they act as a single globally coordinated fleet and they're smart enough to only path through and attack systems that they're reasonably confident they can take; if they're not strong enough, they just stay home. Hence they survive better and accumulate to far greater numbers than the AI-friendly ones which attack your planets one-by-one and die.
So, I'm imagining what Preservation Wardens would be like if they wandered around AI territory at random but never deliberately entered your territory. I feel like they'd be really annoying, because you'd constantly be having one show up in the middle of doing something else, and then you have to stop what you're doing and go fight the drones it spawned and try to kill it before it leaves. It'll break up the monotony of clearing a planet, but would itself become monotonous, while not being nearly as scary as a single global SF fleet coming for you.