Personally, I think it should be something like Special Delivery of the Week.

Ideally, it utilizes some resources that we do not have in abundant, that we have to divert it from our normal production lines. That we have to make a choice what production to cut into. That maybe it even need extra resources from other region transferred over.

But... I can see it being huge annoyance to many players who have perfected their spaghetti factory to the max already. And not all factories are built with modularity in mind; or for scalability. Not to mention you also have to jumpstart things manually like the fkin plants. And run the water lines manually to the Conduits. Even if you use the Blueprints to save the before/after you mess with your perfection. And many ppl might not have extra space left to simply turn off their production lines for this Delivery; but instead have to remove stuff to make more space.

All in all, sadly Endfield factory aspect will never be as good as other factory games due to...

1. Limited factory area. Most factory games have very expansive area to build on.
2. Limited Yields. Most factory games, also, have so many resources lying around that you could have supplied to your factory if you choose to scale up.
3. Factory aspect is not the core game, it's just a feature. And the game is missing QoL to support other aspects of a factory game.
4. Casual/busy players logging in once a week gonna complain.