[X] The Unbroken Few. The seven comrades who stood with him against Necare, last survivors of a brotherhood chosen for their lack of remaining ties as much as their quality.
[X] A Grim Reprise. Mortarion shall hold his own funeral, and that of all who follow him. Barbarus shall mourn the deaths of those who go to the stars, but they shall also be proud, for it will be a worthy end indeed.
The Emperor grates on us, it seems, but not so much that we need lose sleep. His way will not be ours but if that was a sin the whole of the galaxy would be damned for that alone. If he can not see men as men then we shall see them for him, performing the labor he is ill suited for. Perhaps he knew this when he created us, recognizing his limits and siring those who can surpass him within their narrow facet.
We see his flaws and... perhaps that is comforting from one angle even if it is irritating from another.
We should draw up planetary optimization protocols once we are put in touch with the Genetors of the Mechanicus: A catalogue of biological and technological elements known presently and acquired over the course of the Crusade that can be applied to our worlds to bring them more fully into habitable range.
Even in places like Hive Worlds which normally don't have an environment this would be of massive use. Imagine bioremediation-focused ecologies that can be implanted into the Underhive that can scrub toxic and mutagenic substances out of the environment, or on the surface outright eating the sulfur compounds that would otherwise sterilize the landscape through the production of comedically potent acid rain.
We have millions of worlds to sift useful species from, including legacy species from the Dark Age of Technology, even before we turn to splicing and whole cloth genetic engineering.
The holy grail is probably finding a method of preventing ork fungal substrate from, you know, producing orks. Either by providing a biological counter to it, preventing it from ever developing to the point it even CAN make orcs, or else by creating some neutered variant that out-competes the normal fungus while not having the same end products. But that is probably so goddamn far down the road that its not worth worrying about right now.
Regardless, the more worlds we have as a polity the better conglomerate ecologies we can build. And I would not be shy about ripping off Eldar Maiden Worlds in the least. Eldar have been doing this longer and, while using their tech is politically unfeasible, stealing their trees is just good business.