I guess I'm getting jaded. I used to jump on turn-based space games, but none of these look all that appealing to me. Falling Frontier isn't even turn-based (although rtwp and slow pacing like Stellaris uses isn't that bad). Alliance of the Sacred Suns looks like a boring empire sim like Crusader Kings (albeit turn-based, if the "next turn" button on one of the screens is to be believed). Terra Invicta appears to have simultaneous turn-based combat, but it's hard to say if they don't mention it. Not that it matters. All three of these games look like the sort of thing where you spend most of your time staring at stat screens, which isn't really all that much fun to me.
Also, all three games mention modding. Is that modding via a closed-to-gog Steam Workshop?
I really wish there was a sci-fi strategy like HoMM or Disciples. Turn based, easy to learn, not much focus on economy... sci-fi strategies seem to almost always be these huge, sprawling, super involved behemoths that immediately frighten me off. Real time also, so it can be even more overwhelming.
Maybe AoW Planetfall? I don't really care for the WH/WH40k universe, but maybe WH40k Gladius?