Well, I'm not crazy about the name 'World Governing Entity.' Something catchier like... "Unigov" (a colloquialism) or UGO (United Global Order), maybe? Whatever, small beans, I guess, but I can be a stickler about trivial nonsense. =P

I'm a bit curious how a desolate, war-torn, resource-poor Earth would be able to come out the victor in a war against a technocratic, resource-rich Mars, save perhaps by a combo of some sort of "space race" scenario to claim the rest of what the Solar System has left to offer and just outright seizing Martian vassals and pillaging their goodies. Is that the way of things?

I also fail to see why Mars would even bother with Earth during its own golden age, but as I don't see any mention of it in the truncated sheet, maybe you've dropped that.

I'm wondering if the Grand Coalition would evolve into a less greedy-by-necessity society driven by desperate conquest and consumption and more of a market-based one that values trade and innovation, especially as humanity ventures beyond its home system and reaps the benefits of others.

And hey, where's the AI that's gained self-awareness? Can't have a space opera without at least one. ;)

Anyway, mostly dig it. Like 90-95% of it. ;)