I still think having a minor faction respond in a "hacking" fashion doesn't fall into either "while netflix is downloading" or "more AI treadmill stuff" category.
I agree with this.
Keith, you don't want to make the resource finite like Knowledge, and you don't want it to be infinite either because then people can just AFK without any consequence.
The Cynetic suggestion elegantly solves both of those problems. Oh, feel free to afk and harvest Cynetic. But when you lose that planet you've been harvesting from for 3 hours, expect a helluva fight.
You make it sound like it would be overly complex but it's not. It's not more complex than the current ARS Hacking mechanics. The game would even tell you at the top left what the AI's response would be just like for ARS Hacking attempts:
AI's expected response to more Cynetic Hacking on Planet Murdoch: Low.
AI's expected response to more Cynetic Hacking on Planet Earth: High.
The type of Stronghold build would depend on the amount of Cynetic Hacked from the planet in question, with an AI Progress multiplier. So, for example, each "Tier" of Stronghold would have a threshold of Cynetic hacked. Say it's 200, 400, 600, 800, 1000. When you cross this threshold, you get the nastier Strongholds. AIP simply acts like a multiplier. Reaching 100 AIP means it's a 1.0x multiplier, anything below 100 AIP lowers the multiplier. 150 AIP may be like a 1.25x multiplier etc. These determine your total "Stronghold" score, which determines what type of Stronghold the AI will build, and how quickly they will build Guard Posts on the taken planet.
The problem I have with just a "Increase AI Fleet Size" suggestion is that, well, primarily it's boring. We already have a number of mechanics which already do that. Plus we tried that with Champions, and quite frankly, it didn't work. For some players it was making the game unnecessarily hard, for others, it seemed to make no difference at all. And besides that, it's an "invisible" mechanic. If we're going to make this new "resource" mechanic something powerful, then the player should directly realize the consequence of mining it, because that's more fun.
And when you think about it, if the only thing the new "Crystal" is doing is making your defenses about 10% stronger (with the Military Builder), but also making the AI 10% stronger overall...then haven't you basically accomplished nothing? Those two mechanics just cancel each other out which makes using the entire thing pointless. I would just avoid it altogether.
With the Cynetic mechanic, you have the ABILITY as the player to ONLY benefit from the new resource for the entire game. It is UP TO YOU how powerful it is. But on the flip side, it can also cause you to lose the game if you become too greedy. It isn't just a convergence of factors that cancel each other out, it is under the player's control, and adds a whole new layer of strategy to the game.