For me as a GM this is a nightmare scenario. You want me to not only manage story, NPCs, physics, metaphysics, narrative cohesion, pacing, world building, encounter design and scheduling, I now have to make your rolls too? Miss me with that shit.
I would turn this around: If there is trust [to not meta game] there is no need for the GM to make any rolls or have hidden stat blocks for any NPCs. This way the GM can focus more on roleplay.