I was reading the lore on the main site, talking about the collapse of the gate network and how it fractured civilization and a thought popped into my head. It's probably been talked about, but I couldn't find it (there's a lot of posts with "gate" in them).
When the player re-activates or uses a gate, they might have the option to catapult their fleet to long-lost worlds or completely alien landscapes. In these remote locales, your fleet is all alone and against whatever might live there - organic space monsters, ancient crystalline ships, sentient insects, infernal hellscapes, etc. The possibilities would be endless.
You go into the gate with whatever your fleet can carry, without any kind of support structure. You don't know what's on the other side until you warp in. You stay as long as you can and carry out whatever spoils you acquire, from technology that can't be reproduced to unique ships or special officers with unique skills. You never return to the same remote space twice. Activating the gates for these trips could be quests in themselves or cost prohibitive so players don't just return over and over and over.
The risk is in potentially leaving yourself stranded in an alien world with no way home (hope you made a good save first), but the rewards could be great.
I'd pay for something like that as a DLC content expansion.