Janus
I mean, I liked the idea that since they're twins, and the fate of Galaxy was pretty much openly presented to them and they had to make a choice, each would make a different one. Would bring the "team-killing Horus Fuckup" to another level, and bring credibility to the idea that Emperor continued existence (which I also liked to blame on regular badass Guardsman Ollanius showing up, but GW made me hate that character as well) that is however without ability to do much was the third option that was not predicted, further establishing uncertainty, that despite the Grim Darkness of "there are no heroes, nothing can change the world" a right man in the wrong place can make all the difference, and future of 40K can go either way, since things suddenly were not just as planned.
Reading the allies matrix it just struck me that the Sisters of Battle despise all xenos & chaos factions (that's a given) and consider Imperial Guard units to be battle brothers (that's adorable), and they consider all space marines and grey knights untrustworthy allies of convenience or worse (that's wise. But also surprising).
Regular badass unite.
I also find it hilarious that the Emps made space marines so humanity would have these power armoured supersoldiers, but because they were reliant on humanity for continued existence they wouldn't rebel. Then they do the worst rebellion the Imperium had ever experienced and ruin everything for the next 10,000 years.
The SOB meanwhile are just regular humans in power armour. Not only do they do the same job without augmentation as the space marines, but they also didn't instantly become team killing fucktards despite having none of the biological limitations / dependencies of space marines.
Space marines suck, the Emperor should have just made SOB legions from the start
The problem is Space Marines served as spearhead for newborn Imperium, and met a lot of really crazy shit along the way. Would Sororitas have their own Heresy is really an open question, and there is the point that perceived Sisters resistance to Chaos comes from sexual deprivation and a lot of topless images of Emperor when he still had flesh on him (though the latter part is not necessary), in other words, faith. Emperor is not a fan of that sort of thing.
Oh, the Sisters of Battle would have done a fine job conquering and even ruling the Imperium, but that was not what the Emperor wanted. Building the Imperium was what the little people did with the rubble left behind from his galaxy-spanning genocide spree, because he was a bloodthirsty monster. Whether or not he actually was Alexander the Great, he certainly had the ego to see himself as an Alexander-like figure and therefore to view Alexander's troops' refusal to conquer India, however apocryphal, as a cautionary tale: men would eventually grow weary of war.
You know, I don't think you are wrong with bloodthirsty monster as much as with the entirety of your argument. Emperor ain't human. He's an artificially created being, and he does thirst for blood of xenos for pretty obvious reasons.
Space Marines are not men. They have their humanity cut out to make room for more organs, and the Primarchs are doubly far removed. They do not grow too old to fight, and have no desire to do anything else -- reinforced, in extremis, by all those biological dependencies. Nor are they even designed to do the calmer parts of war. Logistics is what serfs are for.
That's kind of wrong. Marines do get older, though it's nearly impossible to see one really old, due to occupational hazards, and some of them do really well in terms of peace stuff (see, Ultrasmurfs, but to be fair,
they're amazing at everything, so that shouldn't come as a surprise, eh?).
Plan A was to purify the galaxy at the head of a band of superhuman weapons who'd laud his victories, share in his bloodshed and regard him as their literal father to be adulated even for genocide.
Utterly wrong.
Plan B was to replace those original twenty bros with smaller, less superhuman mini-bros, but to have lots and lots of them to cheer him on to make up for it. Plan B.2 involved the human-built Webway, and I am still not entirely convinced that its collapse and the subsequent never-ending battle on Terra was entirely an accident.
Wrong even more. Emperor couldn't give less of a shit about being lauded, liked, loved, cheered. This is actually a major fucking point for why Heresy happened, and more recently, Guillman rude awakening that Emperor was pretending to be nice all along. He doesn't even regard Marines (And "twenty bros" even less, since they were never regular humans to begin with) as full human beings, but tools he needed to create the spread and protect humanity across the stars. Big E has certainly many flaws, but nearly all of them stem not from being bloodthirsty for the sake of it, but from what is essentially his hardcoded purpose of protecting humanity. If the protection requires him to go on a Galaxy wide crusade to unite humanity once more, and wipe out the threats, so be it, but he will need some help.
No way dude, psykers are the most susceptible- that's why librarians have to wear the hoods. As you said above, Grey Knights owe their resistance to the psychic bond. Every member of the squad is being continually monitored by every other member... Much like some kind of gestalt GSC hive mind. I mean, they can also merge themselves in order to cast spells, something no other humans can seemingly do.
You don't need to be a hive mind to monitor every other member if you're a psyker. That's generally what psykers do, look into other people's heads. Also, what you said about no other humans doing it is extremely fucking dumb, and casting together is prevalent, if not on battlefield, Astropaths are probably one of (if not THE) most common forms of Psykers across the Imperium, and they constantly do Astropathic Choirs. Or are you telling me Astropaths are fucking hive mind too?
If you take it to the tabletop, it becomes even more glaring. The difference between an imperial guardsman and a genestealer neophyte guardsman? a floating +1 Leadership.
The difference between a Space Marine and a Grey Knight? the same +1 Leadership.
Stop using tabletop as arguments for lore. It doesn't work, it never did, and never will. Tabletop is so vague that you never know why exactly a thing has this number ascribed to it, but not the other, and this argument essentially equates that EVERYTHING with +1 leadership over the standard version is a hive mind.
ALSO GAME WHEN RELASE THE GAME AAAA GIVE ME IT GIVE ME IT GIVE ME THE GAME AAAAA IT STILL NOT OUT
SEEMS LIKE STILL 6 HOURS AHHHHH HELP ME