I recall the tutorial saying you would typically take 30-40 planets on an 80 planet map. Well, I'm clearly playing the game VERY differently.
In an AI sector there are very few mobile threats bar the odd patrol, and a massive wedge of ships deals with them no problem without breaking its stride. Plus, the less planets you have the more defensible you become which is important considering the turret caps. A large territory looks self-defeating to me, as you expand you increase AI Progress so need to destroy warp gates to limit attack vectors which in turn leads to bigger and bigger attacks as AI Progress increases.
Meanwhile the caps on ships means I've never found much of a need for more than a normal docks and an advanced factory, this still allows me to pump out huge forces which I busy myself with scouting and territory maintenance.
At the start of the game it's about establishing a resource base, taking six or seven nearby high resource areas and one advanced factory, but once that's done I never feel a need to expand my base. I don't worry about advanced research because it takes a lot of knowledge to make a new ship useful and I'd prefer to spend that on existing tech. I might clear out ion cannons in sectors I need to travel, and my ships will destroy command posts too close to the warp routes, but that's it. There's simply very little threat in an AI sector which stops you from merrily sending forces from base to their target eight hops away. Of a force of 500 ships I'd expect to lose twenty to thirty en-route, leaving me with more than enough to destroy almost any target I might have in mind (usually a data centre).
Finally when the time comes to destroy the enemy homeworld I'll clear out the sector before it and send ships there in the hundreds and once I'm at critical mass, launch in.
I suppose I just don't see the point in masses of planets which are only a danger to me, I seem to get enough resources from seven or eight planets for everything except starships.
On difficulty seven I'm easily able to replace losses from raids and rebuild forces so I don't need more planets. Perhaps on higher difficulties, but it's just so easy to move through unmined enemy sectors, and if they are mined usually a counter-sniper, tachyon drone and a few turrets will do the job and keep the route safe.
I've been (perhaps prematurely, I'm going to fiddle the difficulty in other ways, higher progress, more aggressive personalities) thinking of ways to give me more reasons to expand. At first I thought higher AI progress would means I needed the resources to get out there, but my problem with that is it devalues data centres since by the time you've built a force and destroyed the centre, you've probably regained most of that progress in auto-AI progress. What I think would make for an interesting trial is the ability to link the AI progress to the number of planets the AI owns, with most of the galaxy under its control the AI progress counter ticks up pretty quick, so in response you take out planets and suffer the short-term hit of a progress gain while getting the long-term bonus of slowing the automatic-progress. This would probably hit a critical point mid-game where you've slowed the progress but taken a lot of boosts from taking over sectors and now need to launch some desperate raids against data centres to get it down before you're overwhelmed.
This gives the player damn good reason to expand and brings command posts more into play than they are now, but an obvious couple of downsides are that there's a danger of the game peaking prior to the end, the point where you've slowed AI progress down and own your territory and also it plays contrary to the game's intention of the AI becoming more and more deadly as the game progresses. Still, the way I play at the moment and the opponents I have faced the most difficulty point was protecting my first sector and I've been pretty safe after that.
I'm going to try some more aggressive opponents in my next game though, they would need to destroy more than I can build and thus force me to expand for additional resources. Currently I easily outproduce raid losses which is why I don't need to expand.
