Hm, so closest I'm getting is "Warsaw Pact without an opposing NATO or USA". I'm gonna stop analogies now since I doubt there's one that will fit well anyway, and just say that I understand. 

Alrighty on tech. So nitty gritty, kinetics and missiles for weapons, with maybe lasers for point defense purposes (Like what they had on the Boeing YAL-1 before the project was scrapped) Not too effective cause space is big, and you couldn't kill a ship with it. Prosthetics exist but are bulky, not smooth streamlined and nearly indistinguishable from flesh and blood. Maybe drone fighters, if those are effective at the kind of combat distances that would be involved.

Great minds think alike apparently, I was going to mention the Alcubierre Drive myself. Besides, perhaps, nBSG point to point travel, however that might work, the alternative I can think of is a 'Mass Effect' type system. Namely, FTL exists, but it isn't particularly fast. So to travel, say, across the galaxy, you have to use these structures we'll call 'Stargates', for lack of a better term. These stargates are large structures with the power and capability to create wormholes between itself and other gates. They're generally guarded by space stations or automated turrets too. It provides choke points that the Nexus could theoretically use to keep sway over chunks of the galaxy. I dunno

Anyway, still interested, either as the espionage specialist (I have good ideas for this), or the engineer.