Was thinking for a bit about those, long ago when I sued to play mass effect games, especially 1 and 2 had to me a great build in forming up the Who is who and what is what even though the series were unfortunately filled with more and more of ideology, thus dissonance with each iteration (2007-2010-2012)
For a campaign of any depth, you will need to have a multitude of factions, their interests, them asserting themselves.
Since planets are something like cities, countries made up of multiple cities, plus the rest of the environment. I am really interested in how the writers (hopefully not self-writing done by machines 
still something REALLY creative or somewhat feasible)
Mass effect series projected their ruling class ruling the earth under 1 world govt tyranny, how fancy of them. At least this is how they portrayed their wish to rule over everybody without their inputs Rather brazen though that was 18 years ago. ('Systems alliance')
Notions like galaxy factions using money that TEC factions can steal via a reserve currency which they somehow imposed on everybody else using money is also rather rich. Nobody sovereign and aware of how using something that can be used by the enemy against them, as something, from somewhere, would be too unintelligent and complacent. Too much fancy stuff, that implies TEC rules by proxy over all the factions, be they vasaris, advents, tecs. Adversarial TEC factions stealing money from each other, because each uses the same money issued by who ? They got both printing presses and they produce the same money So they steal from each other
Your ability to steal money if adversaries use them, should only be tied to having brainwash superiority aka information control over adversarial planets. Meaning, against their best senses (vassalization, taking over by bribery selling out their own people) they are persuaded to use a weapon of the enemy against themselves, though it should be vassals primarily who finance the empire. Because only vassals will use your currency, in order for you to export inflation, (in effect taxation/tribute system) so that your TEC corporatists can live above their means. (refusing to negotiate for example, more money for them hahaaha 
) If money/gold is not used instead of fake valueless money which are best used to swindle producers of real goods by stealing (most) all the value they made from them this is an incentive for a degeneration of a state entity which in time/under stress will collapse. Because it turns into total dependents to its colonies/vassals. Once those are cut off, (you cant tax the vassals into taking your expenses) the artificially alive imperial center does not have support to keep itself alive, it lost skills and cadres, the personnel who could keep the state machine going and they in their greed destroyed their own economy first. Who could make this stuff up ? 
Swindling enemies into buying debts (getting taxed by an enemy no less) of an financial capitalist empire, production of everything of value shifts to the vassals while the imperial center hollows out and is run on total fake of an economy for a time. Until reality hits and it collapses. Because it exporting money (nothing) and getting everything of value back to them is not viable long-term.
Making up all sorts of factions resemble real behavior instead of the trotskyite 'we need to unite' with our 'permanent revolushon' (like the one tied to volfovic doctrine) with 'Aliens are coming' edition instead. I mean thats the 'emergency' coalition about right ? That is the narrative being rehashed over and over. Real politics and relations between (really, not on paper) sovereign nations are more complex than that.
Usually then as it comes with these political/sci-fi tropes, aliens are coming to either wipe out and irreparably corrupt what is left. Poor aliens are always poured on so that actual bad folks can hide, often on pedestals.
Instead of total doom/gloom end of times narratives, which is what these types of games come up with, you could look up something more realistic, not the wishful dysto/utopias of say RAND and their Extending RF 2019 document on corporate 'spreading Freedom', if you need inspirations, those arent found in media and in most cases these would be sealed off and forbidden for a 100 years and similar to get in public. On YT there is a channel called Dialogue Works and guests like John Helmer gives there his ideas and perceptions on things, then B.Berletic, his -The New Atlas, who documents how certain countries subversion works in great detail. Extremely educational and great material for widening your horizons, so that whoever writes script for the game, does not end up like a frog on the bottom of a well, thinking they see the whole sky. Economists there like Michael Wolff and Michael Hudson give also very varied perspectives. NOT found in 'media' And what amounts to 'education' designed to mislead and hide. Ret. Col. Wilkerson and fmr. CIA Larry Johnson is mostly interesting to listen to, most objective from my observations. There are others, but as far as I'm able to say, the most objective of analysts.
End of history did not happen, not yet at least
I hope I provided some good ideas on how reality works here and there, so that things like economy can actually be understood.
ME 1 for example did set out the stories of big corpos doing their businesses in whatever planets and so on, it felt very lively, not that far removed from realities of basically, power politics. (where corpos really do hold power to a large extent) And about who can do instead of talk a big game. Thats what big imperial conflicts or cooperation happens about, resources and stuff. Possibilities there are so great for very good writing, the space setting is just really a setting for these. How it is presented, how much in depth you go, if you are able to make a big narrative even in an RTS setting, it will be great. But for that setting, so on, what do you think, at least in the campaigns, if planetary objects got increase in radius + 100% Scale of planetary objects, things become less gamey. But those textures will will look low-res. Maybe. Try it out. How does it feel ? Space setting, does the space look realistic ? Or is it 'AI' 'painted' ? Try it in the campaign setting how does it change the perception of scale. Space is really big and any space objects IRL are gargantuan compared to whatever youre 'building' in space. Yes, its a game, but if you want to tell a somewhat believable story, In Space, not just in a Space setting, the setting has to be believable, so that one helps and multiplies the effect.
For me ME1 and 2 were very memorable, 3 not so much, (I did play MP there quite a lot) Maybe it was different writers, that made different impressions. 1 built up the setting. 2 used it and 3 was so-so, (ideology was trying to beat you left and right into submission in the meantime in 3 big time, trying to break what is normal and what is not and mix them up into disorder to damage you ultimately, oh what is good or bad is 'unknowable', sudden rush of agnosticism, while not using the same standard elsewhere)
Yes I know I write all over the place most of the time. You should not look at the form, but at the contents Yes, I do simulate counter-arguments which I did get in real conversations with some people and those rationalizations they came up with, so it is not me asking and answering my own internal questions
Cheers
