[Suicide Junkie]

PVK:
"That is, supply storage _IS_ like an engine that just "generates" supplies. At least, that's how I try to make sense of it."

Ah HA!
I think I see our problem. You see supplies as power (reactors), while I see them as fuel.

I am curious as to how your reactor model explains "running out of supplies" and the fact that even one supply component can use all of its supplies anywhere from instantly to year-long spans.

There are mods which change supplies into reactor power, by having reactors that generate as much as they can store each turn.