I'm calling it now, the player will be able to transform into other superpowered beings/monsters to literally be able to use every superpower by the end of the game.
I think on the corruption path the MC has eaten all essential spawns and monsters to have all six of the original powers.
The powers of the Arbiters or Origins. Ella seems obsessed with perfect evolutions, if being a perfect evolution means you inherited the powers of both twin Apostles you inherit the power of the Origin... (The eye does not except the authority of the first, not because he's stronger but because he's higher level, the Apostles are next generation, offspring to the Origins)
On the no corruption path MC will be one of up to six superhumans with each an original power... Michael and Alice seem likely candidates to be 2 others with an original power, Amber or Liz might be another possibility (my guess Liz, she excels in everything lol) due to the fact it seems likely they're gonna be kidnapped to serve as permanent bodies for 2 Apostles...
That would cover 4, the other 2? Pure speculation but i think Charlie will be another, Shopkeep supports her so she's important.
Either Claudia or Tiffany seems a valid option, although Tiffany sooner as candidate for eating, she's too powerhungry..
But i could see MC ending up with 2 or even more original powers simply by defeating certain monsters, the son of Deryl and Aglaecwif seems a likely candidate for that, the power of the Apostle of Aglaecwif and Rebis... Valravn another...
In the end S.I.N. (or what's left of it) and HERO will fight together, the Dark Lord will be the enemy...
He's been trying to do the same, killing Gods, eating Apostles to get all 6 original powers...
Deus needs Ella to complete her work, to get out of this mess.... The 6 original powers are the key to stopping the monster invasion.... (Or to let it happen and rule them on the corruption path... )
Edit : I could even see MC's original power being "Unity" and he can combine the power of 2 superhumans to have excess to their original power, like Jake + Michael = Order...