This looks interesting. Is it basically you just playing a longer version of X-COM where you play through the backstory a little bit before the aliens arrive? Seems interesting from a roleplay standpoint, at least.
I jut spent a couple days with the demo.
The actual gameplay is nothing like X-Com. There is no squad-based combat: such things are far beneath you.
It is more like a mix between Hearts of Iron and Kerbal Space Program. Both Earth and Space are critical to success. Earth is where money, research and influence are coming from. You will be fighting a political, and often even regular, war there. Space is where you will confront aliens... and other human factions.
On Earth, beginning of the game is a mad scramble to take control of nations. Aliens won't actually be doing much in the beginning and instead you will be struggling against other human factions, where wage combat using whole national armies. In fact, so far I've seen far more humans murdered by humans. Humans are not united, are complete jerks towards each other, committed to their nationalistic prejudices, willing to commit outright genocide in name of their ideologies and, unlike most strategy games set up in modern time, nukes are there, can fall into hands of extremists (usually, player is the worst) and are horrifyingly destructive. In demo, it is not uncommon to have billions dead before aliens even fire a shot.
Now on to space:
The solar system is insanely well modelled. There are 350 objects: planets, dwarf planets, satellites, asteroids, etc. All of them have proper orbits: none of the orbits are circles, but are actual elliptical orbits. Planets are not much inclined against plane of ecliptic, so, as in real solar system, are mostly in 2 dimensions, but Kuiper Belt objects and many asteroids are inclined. Of course, all the objects are in motion with their respective orbital periods, so your strategic map drastically changes all the time. I literally spent an hour with my 5 year old simply looking at the solar system. He told me that one of Saturn satellites was a pancake. I zoomed in and indeed it was a pancake, which is bizarre. Turns out it is really a pancake:
https://en.wikipedia.org/wiki/Atlas_(moon). Seriously, I cannot recall anything even close to this. It is far easier to show to a kid than the system on the freaking NASA website! I would literally buy the game just for that!
Actual travel in space is also realistically modelled. Stuff needs to be transferred from Earth to Low Earth Orbit. From there, it needs sufficient escape velocity to continue journey. All planets and major satellites have their 5 Lagrange Points where you park stuff and do re-supply. To get from Earth to Mars, you don't just fly there, you do a Hohmann Transfer (
https://en.wikipedia.org/wiki/Hohmann_transfer_orbit) instead. Which means that to have a reasonable travel, you must launch within the launch window when orbits align for easier transfer. Earth orbital period is a year, Mars is 1.88 years, Jupiter is 11.86 years, so good luck timing!
Now, on to factions. While devs did not talk much about them, I did some digging in game files (much like Paradox games, a lot of parameters are in plain text and are easily editable) and what I saw matched behavior that other players observed. I will talk about 2 parameters here: "protect human life" and "Protect Alien Life", which range from 0 to 1. There are 7 human factions + aliens. Keep in mind that all 7 human factions will be playable.
1. Resistance: basically your standard X-com guys. Protect Human Life is 1, Protect Alien Life is 0. Moving on.
2. Protectorate: believe that humans are doomed in war against inter-stellar civilization and thus seek to negotiate a peace/surrender on terms where humanity can survive. They are quite pacifist with Protect Human Life at 1, Protect Alien Life at 0.9. During demo, they were mostly just sitting there. Useless in fight, but at least wont do crap that # 6 and 7 in this list will do.
3. Academy: they believe that humanity needs to convince aliens that we are equals and ally to them. Protect Human Life is 0.85, Protect Alien Life is 0.85.
4. Exodus: believe that humans have no hope in fight and also that aliens will not spare us. So, they want to escape from the Solar System. Protect Human Life is 0.85, Protect Alien Life is 0
5. Initiative: ruthless capitalists/Illuminati who seek to use chaos for personal benefit and become the dominant power after the whole thing is over. Protect Human Life is 0.5, Protect Alien Life is 0.5. In other words, they are perfectly OK with murder for sake of profit.
6. Servants: now, this is where things get interesting. They worship aliens and will actively help aliens conquer the Earth. Protect Human Life is 0.5, Protect Alien Life is 1. In other words, they will willingly kill humans if that saves alien lives. Now, remember what I mentioned about nukes being nukes? Russia and USA got a LOT of nukes. If said nukes fly, humans will be far less capable of resisting, won't they? And aliens are not here yet, so they don't get hurt... And this is a faction you will be able to play!
7. Humanity First. Just like Resistance, they want to fight the aliens. In fact, more so since they really want to kill all aliens. Also, kill all traitors. They are a really violent X-Com. Of course, Protect Alien Life is 0. Protect Human Life is... 0.5. Yep, they place no more value on human life than a faction actively supporting aliens. If they get hold of USA or Russia... they got a GREAT set of tools to teach traitors a lesson. Lesson that will wipe out half of Earth GDP and third of population.
Finally aliens have Protect Alien Life at 1 and Protect Human Life at 0.25. Quite curiously, they seem to be more OK with humans than resistance is with aliens.