Hi @Dracu good first post
My 2 cents on stuff you said
Oni is a what if scenario, a possible end of the road for him… Oni is very likely superior to current Akuma in a imaginary direct fight scenario.
Akuma may have a slighty edge if we speak about technique/control, but the difference as raw energy is probably so much that finesse or not Oni will just overpower through Akuma
But Oni will also be a “only” a demon, a beast that just follow his own SnH flow, he will be the physical incarnation of that corrupted ki, without much of self awareness and will.
He will be a powerful but still limited monster, well below the kind of war deity Akuma wish to become.
Fun thing are how quote show Akuma and Oni disprect “each other”
Oni intro vs Akuma “Fool, I’ve evolved beyond you*”
Oni defeat Akuma " Farewell. This is Oni’s world"
Oni quote show he see Akuma (his past) as an obstacle to reach the Oni path, that’s because Akuma’s objective is not to become Oni
But tbh story is’nt even consistent, example in SFV Gen warned Akuma he will never reach divine level negating it’s human side, and there Akuma’s reply seem to have him full into “bro i want become a demon” shit
So at the end it’s not that Akuma don’t want to become Oni, he probably simply does’nt want to stop there and keep rising to and beyond deity level, while others like Ryu or Gen think he will fail at it (with Oni being the final of his path)
I think become “Q” will be the punishment inflicted to G by somebody (Illuminati i guess) for his ambition in SFV.
I agree that G ultimate plan may be turn “citizien of earth” into masked human marionettes…
…wich will make even more ironic if end up his punishment to become the same thing