If the threat is 'other humans', you may as well just make it any other sci-fi. The problem with Necrons and Tyranids, unfortunately, is that the Terminator franchise already exists, and GW can't 'copy' Starship Troopers. And by Drukhari, I mean 'Elven Space Pirates with Body Horror', with no further depth than that. To be '40K for normies', I really think the antagonist - or threat - needs to be Necrons, Tyranids or Drukhari. But 'It's not 40K.' It's classic Dan Abnett, and I just don't think Abnett's stories are 'right' for mainstream audiences, whilst still feeling like 40K. Nope, just those corrupted humans who summon daemons who are so obviously evil you don't need to go into depth on why they need to be stopped. No juggling Necrons, Tyranids, Tau, and more in one setting. It's mostly just Chaos with the occasional Ork interlude. Their opponents aren't too insane either. You don't really see the facism and evil corruption of the Imperium, unless that's the antagonist to be fought.ДЄnd the cast is both relatively self-contained, unlike the Horus Heresy where you've got dozens of characters who never interact with each other, and very relatable. You only see allied Space Marines as these super soldiers coming in to either save the day or as the evil warlord's top body guards, none of the backstory of how they are brainwashed child soldiers abducted from their home planet.

It's 40K, but only lightly touches on the evils of the Imperium. But at the same time, their own allies are cruel, vicious, and treacherous, being more concerned with glory than protecting the people, and willing to sacrifice millions just so they can claim victory. And they are fighting against a really obvious evil, with the demon worshipping cultists being their opponents. The good guys are obvious, the human soldiers. That's more or less why they should do Gaunt's Ghosts instead.

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