I'm going to be blunt and say it outright:
Don't do this.
>A first-time project that attempts to ambitiously anticipate for a rank of powers that hasn't even been determined at this point, and a passive where such powers need to be active
>in a locale type that frankly is getting overcrowded (too many forgotten temples on the slate already),
>with multiple perks that reach into the guts of at least one core system,
>an entire sub-zone with multiple NPCs,
>with combat that frankly, we usually discuss and revamp according to our own needs anyways.
Might you be the one to emerge on the other side without burning out, flaking, moving onto something else, or wandering off into limbo? Maybe, but the graveyard of JimT continuations and numerous fresh faces buried within alongside their ambitious projects suggest that the chances aren't good.
Do something smaller, work with us for some months, understand how things work, then maybe rethink this and give it another shot with some different wrapping.