We have a system which punished you for being big but doesn't make it hard to get big. This is exactly the wrong way around - it should be hard to get big, but being big should be worth it in the end. A rising maintenance penalty per colony would do the trick; expanding too rapidly would bankrupt you, but having lots of highly developed worlds would make you powerful.
I disagree. This is exactly the right way to do it. When it's done right that is...
It shouldn't be inherently easier to make a "taller" or "wider" empires. It's supposed to be a strategic choice. And the main point of "punishing for size" is making the management of the size a gameplay element.
Well since I wanted to post something helpful.
All colonies should have TWO different kinds of population: residents and colonists.
Colonists "grow" from population, and when you take them into your colony ship, they are gone and you can't take more people.
Or call them "adventurers" and they can be soldiers too... Just don't make them unlimited.
Might as well emulate ship rebelions, separatist factions, elections, royal inheritance, civil wars and ruler marriage. Yeah right...
NOT happening. And that's a good thing.
I fully disagree. Each colony should be self sufficient and there should be no increased maintenance. If the imperium of man can have a million worlds, so can you. As for gameply perspective, if all you're doing is expanding than you're very vulnerable to being attacked and having your colonies stolen. I'd rather see Transports being unlocked from the start as a solution than increased maintenance, because as long as you make some wealth planets, the maintenance won't bother you at all.
If imperium of men doesn't exist neither should this. And it doesn't.
Besides the obviously missed fact that size management is a highly valued gameplay factor, empires of infinite sizes are simply unreasonable. The whole game is built around power struggle (so we can't rule out this factor from the civilizations in question), and power struggle is what makes empires fall apart.
That said, maintenance is a poor detrimental factor. I'd prefer a TM penalty. Possibly along with penalties to other things like influence or population growth or even combat efficiency. C5 had a perfectly working system for that... although they changed it so many times I can't say which exact version was perfectly working by now... Well, at least the concept was more or less the same all the time.
As for expansion vulnerability look at how ES did it. In there everyone starts in "cold war" state, which basically means you can attack anyone and anything as long as it's not within anyone else's borders. And borders didn't appear around a colony for about 30 turns after being founded. Not to mention the ability to kill the colony ships and scouts.
The difference from what we see here was in the fact that while such "hostilities" weren't exactly strengthening neighbourhood ties, they didn't require you to outright declare war on all those pesky neighbours.
Sigh... this is what I miss from ES the most... back in there you didn't stake territory with colony ships, you took it with war fleets and held it with war fleets.
And in here you can't even be sure about the land within your own borders. Honestly, we should be able to kill at least the vermin that have crept into our own territory.
It may look far from the topic, but it isn't. The amount of land you can "stake" is a huge factor, and with stronger AIs behaving as they do now you simply can't allow yourself NOT to grab as many colonies as you can reach.