Why not just have perks that give you Psyker abilites?
Personally, no. Does not want, at all.
Psykers are rare and we are probably gonna be demi-gods anyway by the end, we don't need supernatural abilities, it's just adding insult to injury.
And perks? Psykers, as far as I know, are born with the ability or has it be a part of a mutation.
So either we're born a Psyker, which would feel ridiculous to most of my role's I want to roleplay as, or we mutate, which means it's something that is forced upon us, which again, I would not like as I hated the forced Old World Blues/Lonesome Road/Point Lookout/The Pitt perks.
But that's just me, Psykers are rare, and protagonists are rarer, being both? No thanks.