Honestly I find
@Imrix's arguments pretty compelling.
More than anything I really want a PC who's forced to confront the sins of the Imperium and it's collection of allies and thralls. Oh as a setting element the Imperium is fun, don't get me wrong, and there's definitely something to be said for the Catholic Heavy Metal aesthetic. As well as standing dramatically on top of a war machine, giving a speech about the costs of victory and seriously how bitchin' is this ride.
But that's not the same as saying that the Imperium is good, justified, or even necessary. In many ways, I think, the Imperium is a failure state even by the Emperor's own standards (becoming the "Carrion God" was probably never high on the guy's list of priorities) and while the man himself is...complicated and committed his fair share of sins, it's hard to believe that what humanity has become is something he ever really wanted. Thus:
[X]
The Rebel - The Imperium has always proclaimed itself protector and steward of the million worlds beneath its heel, but you know better. You have seen what the servants of the Aquila have done to your world, heard what they intend if left unchecked, and you have decided; enough. You are a faithful man, but loyalty to a God does not demand loyalty to those who pervert his name, and in the glory of your Exaltation your words are proven right at last. (Dawn)
The "no, fuck
you" option. There's something really really appealing about the character who just digs their heels in in the face of like, literally industrial scale exploitation and oppression and goes "fuck you no, you can't have it". And it'd be nice to have something to prove the lie to "rebels either get glommed by aliens or go all Chaos".
[X]
The Firebrand - The Ecclesiarchy is a putrid corpse, rotted from within by the venal corruption of those who should know better. They have gathered wealth and power and proclaimed their politics sanctioned by the Emperor himself… as though the Saviour of Man would ever debase himself with such base corruption. You spoke out against it, fully expecting to be struck down for your words, only to find that the oldest saying is true indeed; the Emperor protects the virtuous. (Zenith)
Itstrueandheshouldsayit.jpg
Out of all the institutions the Ecclesiarchy is probably the one that's twisted most from the original underpinnings of the Imperium. And I don't say this to approve of GEoM's enforced atheism thing (which, frankly, is super fucking dumb). But rather in the sense that the body which was created to serve as a moral guide to mankind has become stagnant, corrupt, bloated, and ultimately derelict in its duty. There's enough wealth at the upper echelons of the Church to fund countless aid missions, lift hundreds of worlds out of poverty, make life better for uncounted billions but they just...don't.
And that's wrong.
(And also I like the potential of the Firebrand to turn around and jab a finger at the Half-Dead God that made all of this and go "No
you fucked up Father.")
[X]
The Visionary - Humanity has lost so much, and what little remains is guarded jealously by those who enjoy the power it brings. You would see the birthright of mankind restored, and to this end set yourself to studying the dark secrets of history in defiance of the Mechanicus and their enforcers. Such hubris would have been the end of you, but for the benevolence of one who once dreamed as you did, and who saw fit to bless your insane mission with His divine favour. (Twilight)
@Swordomatic is right in that the AdMech gets a lot of play in forum stuff and this is probably the most AdMech-y option. But I'm honestly really really interested in seeing an approach that's less based around "let's call the cogheads all morons and show how We Do It Better" and more something that actually engages with their beliefs. Out of all the associated Adeptus, outside maybe the Astartes, the story of the AdMech is one of lingering scars and deep trauma (they schismed too during the Heresy and this is a universe where those echoes can
linger). They're the stewards and guardians of knowledge in a setting that's already lost so much, where new discoveries can bring new horror.
And what I like about this option is that it's the one where the PC is the kinda guy/girl/other who goes "look anyway".
Something that really engages with the
history of the Imperium y'know? What it's lost, what it's sacrificed, what it did to others, what it did to itself. It's a story very much about grappling with that kind of ancestral stain and doing your best to persist even in the face of fear.
[X]
The Officer - You are master of a ship, a Captain of the Imperial Navy, oftentimes the only contact the far-flung worlds of humanity will have with the wider Imperium for years at a time. You have served as their protector and their voice, and when the darkness came for those in your charge you stood and fought... and, blazing with the light of the divine, found victory in the face of terrible odds. Now, you have a new mission, a higher duty, and you will see it fulfilled. (Eclipse)
i like big boats and i cannot lie
Nah, there's just something viscerally appealing about the guy who was out there in the dark, this little flickering lantern in the ocean of night. Doing his best to do right by his crew, right by these worlds, a favored son of the Imperium who just...had to watch. As again and again and again and again the Imperium inflicted atrocities upon itself, as worlds starved and went cold from neglect, as Admirals and Governors gathered glory and wealth to themselves while the frontier suffered and floundered.
Same echoes as the Rebel really, the kind of character who just went "enough".
Plus starting out with a ship is a super solid location thing and a great vector for a more globetrotting adventure which I'd love.