Looks like mythic fantasy is leading. Huzzah.
If it stays the way it is, I was going to make a thread where we each contribute one piece of information or lore about the setting.
My starting bit would've been:
The Celestial Emperor sits upon his throne. Part-man, part-machine, all divine, he watches over his people and ensures that the gods work together to ensure the smooth running of the world as the techmancer does with his clockwork. His words are holy, his rule is law and his mind works, sped by magical theorems contained within the throne itself.
Seriously, don't do anything as a knockoff/expy of 40K unless you're aiming for the silly tone that it originally had before the grimdark gummed up the works. And don't do it anyway because it works for jokes but falls apart in practice.
'sides, I said it before, there are
much better things to take cues from if you're doing anything related to mythic fantasy.
--
Here's an idea, actually: have a Promethean figure be the original source of magitech; he/she/it taught the first human practitioners of a new system of magic which relied upon precise calculation and careful thought, bearing altogether more relation to the realm of natural philosophy than to the ritualistic and unknowable magics of the world before. These disciples warred against the children of certain gods, who acted on their progenitors' wishes to destroy human knowledge of the source of their power.
But the new magics were strong and easily transmitted to the uninitiated. With their knowledge the mage-inventors of the Second Age crafted wondrous works of bronze and jade, instruments to collect and channel mystic energies through prescribed arrays, allowing even the most base farmer's child to strike at the godblooded and their servants.
Now it is the Fourth Age. Great towers stretch into the heavens, buttressed by sprawling magical diagrams. Galleys cast from iron ply the seas, jetting along more swiftly than even the fastest horse. The products of magic are everywhere, in homes and workplaces, magic turned to the simplest of conveniences. Still, just as it was, so does it continue to be: the root of magic is not easily comprehended, and save a handful of gods and goddesses favorable to humanity, the rest have withdrawn to their stronghold far to the north-east, from which they send forth vast armies of men and constructs bound to their will, led by ever-increasingly powerful children of their lines.
It is a time of prosperous life and hopes for the future, a true dawning of a new era. It is the final twilight of humanity, the jaws of fate closing down upon the handful of true heroes and heroines who remain dedicated to their unending war.
--
Just as an off-the-cuff example. It's got elements of both themes and establishes a very slight skeleton of a setting around which new ideas may be arrayed, leaving open most possibilities. It also establishes two potential underlying super-main plotlines for the party, depending on whether they want to play as "good" or "evil".