Those are indeed features. And both slavery and genocide are officially war crimes. They're only missing torture.*
Ironically, one way of interpreting the Paradox forum rules would actually forbid discussion of the very features built into the game (the wrong interpretation of the Paradox Forum rules, for the record, but I wouldn't expect their mods to be as precise as I).
*Will we be getting an "Enhanced Xeno Interrogation" DLC?
Upon pissing off some xeno slavers, they reminded me via diplomatic channels that my species' children fitted exceptionally well in the smallest of mining tunnels
The Miroslavs began branching out, reaching a hand out to the world - and what they found was not good. Few people were willing to be our friends, and our neighbours assumed we were to be vassals to their mastery. As our science vessels explored the Universe, we found more and more of it to not be in religious harmony, but in discordant strife.
Terrible fury was wrought by those who had excelled in the material world, only to put their material prowess to martial success and hedonistic excess. As the last Miroslav outpost was overcome by the Xantt Consciousness, the Miroslavs withdrew ever deeper into the Isauros system. This one star system was their only bastion, their only citadel, their only homeland - from within it they began to delve into the scientific mysteries that underpinned the divine order. Labs, mines, power plants, research grants and orbital shipyards began their construction in immense earnest, whole barren worlds turned to shining beacons of civilization - and the rest of the galaxy didn't even notice.
Unseen from the galaxy, the Commonwealth of Miroslav spent eternity isolated and content. None could watch their planets, all the while the Miroslavs watched them. Federations formed, whole species rose and disappeared, fleets clashing in titanic battles in the void over reasons that seemed quaint - distant even, distant to the Miroslavs to whom the world had become a fearsome mirror in the ocean, to gaze into the maelstrom and see what was being avoided back at home. The picture above is from some gargantuan federation war over a handful of energy rich planets. The Miroslavs did not get involved, merely watching with an advanced scanner ship to see if the isolated Miroslav colonies so far away from their homeland were safe. Many starved to death and were replaced by robots, but most were satisfied, growing accustomed to the ways of their alien masters. Such power was wielded and lost that it would defy historical documentation, passing into the realm of legend - of the silver schools of warfish that fared the void and stars, destabilizing the veil of reality to render their foes into atomized oblivion. This we watched, this we feared.
The Miroslavs only sent expeditions out to investigate wars or scientific curiosities. No one was allowed access to our star charts, no one allowed to survey the Isauros system - on all star chart maps, only one star was nonexistent. One intervention was when the Dathnak species of gas entities were relocated to a new gas giant, after their old homeworld was irradiated by nuclear bombardment by religious zealots - as religious zealots themselves, the Miroslavs were determined to prove that not all organic zealots were exterminatus-happy.
And so we explored the secrets of the galaxy, bringing them all home to the libraries of the Isauros system - it held only 5 habitable planets, but those 5 were enough. Between Vojislav, New Constantinople, New Jerusalem, Bastion Faithful and the Citadel, the Isauros system was out-researching even the great materialist Empires. For some reason we had an unusually high abundance of maniac genius scientists. This technology was only used to improve the Isauros system, never to strike our neighbours - and so it went unnoticed.
Sometimes we would find ourselves with company on our expeditions. It wasn't always welcome, and one time all expeditions had to be drawn back to Isauros due to our hegemonic neighbours launching great wars to subjugate the Miroslavs. With no Navies and everyone assuming the Isauros Commonwealth of Miroslavs was as backwards as ever - the great navies of the world had to quickly learn why they should leave these 5 planets alone.
They were not prizes to be won. The scientists of the Commonwealth reverse engineered much advanced shielding and weapons technology from the Civilizations of the world before tossing the hulks into the sun.
Pretty soon outsiders began to get the message that this was not a weak Empire to be subjugated.
For most, they have acted too late.
The Miroslav are emerging from their techno-spiritual enlightenment, the Divine Armada is for the first time waking from its slumber, the isolationists are secluded no longer.
Already the first moves are being made to save the long lost Miroslavs, now scattered across the cosmos under alien masters.
The time to bring the new order to the universe approaches.