I put all this in the form:
All factions are good for right now is generating "unity." But once I pick all my traditions and turn on all my edicts, "unity" is basically a useless resource that accumulates into the millions with no way to spend it.
But when you think about it for more than 10 seconds, Unity is not a resource. It's a MEASUREMENT.
I live in the United States. We haven't been very unified for the last several years (your mileage may vary). It's therefore been really hard to get things done in the government. But there have been times (both historically and in my lifetime) when Americans
were unified, and things
did get done quickly: for instance, post- 9/11 or during WW2. Conversely, a country like North Korea is very "unified" in terms of national goals (accomplished through purges and propaganda, among other things), but it experiences significant economic and cultural drawbacks for being that unified.
I think this should be represented in Stellaris with a
percentage measurement of how unified your empire really is: 0-100%. Early game, when you have one species on one planet with dominant ethics (and especially with a prosperous unification origin), unity should be very high. It should be easy to adopt new traditions (the threshold might be 60 or 66% unity with a time cooldown). But once you start colonizing different planets, those settlers will have a different outlook on things than people on the homeworld. Unity will decrease. Adding alien citizens (through conquest, refugees, or migration treaties)--especially ones with different ethics--will decrease unity a lot MORE.
When Unity drops below 50%, an empire should start experiencing governmental problems, which get worse as unity gets lower, until eventually a civil war breaks out. (A "Civil War brewing" situation could start at less than 25% unity.)
Of course, there should be things a player can do to ameliorate these unity hits--constructing buildings, dealing with factions, setting policies, and so on. This could give a real benefit to xenophobic playstyles because purging all the aliens will keep your government more unified! But at the cost of all those pops who could be working jobs. Fanatic xenophiles would have the opposite situation: lots of pops producing goods, but at the cost of a unified government. Migration treaties would become something to really think about: alien immigrants might decrease your unity, but the treaty could also allow all your discontented people to leave for free.
I agree with other comments made here that species really should have their own factions that want species-specific goals (e.g., "Full Citizenship for all Blorgs!"). A faction that isn't being pleased should have a negative impact on unity; ones that are being pleased should have a positive impact. With work and careful management, a player should be able to unify a multispecies empire enough to get things done.
Events should also have an impact on unity. An authoritarian, militaristic empire might get a unity bonus when they declare war on someone else. An egalitarian empire might get a bigger bonus, but only in a defensive war. Building certain megastructures (say, Mega Art Installation or Strategic Coordination Center) might provide a permanent 5% bonus for the rest of the game. Upgrading planetary administration buildings could lessen the unity hit from that particular planet. (Empire unity could even be a weighted average of planetary unity if that would help.) Propaganda edicts could have a real impact on pops' ethics, and thus overall unity.
But most of the events that impact unity should come from
internal politics. Internal politics
should be very, very different for each government type. Monarchies should have to deal with court politics (borrow what you can from CK3). Dictatorial authorities should have to appoint leaders, whereas democratic ones have to deal with the outcomes of elections at every level. (At this point I would like to
repeat what I said in response to "The Vision" about leader caps being arbitrary and absurd and how every leader slot should be filled, lest penalties ensue.
You can't have internal politics without having political players.) Oligarch and Corporate empires would have own, unique internal political games.
In all these cases
faction should be an essential trait of all leaders. It may even partially determine their other traits, just as party affiliation corresponds with agendas IRL. And factions' power should not only correspond to the number of pops aligned with that faction, but also with
how many of that faction's leaders are in positions of power. A North Korea-type dictatorship might have high unity because it only allows one faction, but that very act also severely limits their talent pool. On the other hand, in a democracy, undesirable factions might win elections and force their agenda on an empire. I miss how in previous versions, democratically elected leaders had an agenda to complete if they wanted to be re-elected. We should bring that back and tie it to the faction trait of leaders, which will make the agendas feel a lot less arbitrary.
This can lead to all sorts of storytelling potential. For instance, what if a planet on the edge of a democratic empire receives a ton of alien refugees? If they're unemployed, perhaps the crime rate goes up and the planet elects a xenophobic governor whose agenda is to change the empire's refugee policy. Or if those refugees become a majority, perhaps they elect a governor of their own species whose agenda is to get the republic to declare war on the empire that caused them to become refugees in the first place. What happens if either one of those governors gets elected president? And so on.
TLDR: Unity should be a measure you work to maintain and improve, not a resource. Internal Politics should be a game-within-the-game that is different depending on your government type.
