TL;DR
Saving and immediately stopping the simulation in a multiplayer game would leave all players with exactly the same save file. This save could then be used to reload the game at the exact same point for everyone, removing the need to download the map.


What ?
It would require another kind ...

Here is my 2nd and last try but it's... still bad. Mainly trains, no bots, some belts, smelting off-patch. Smelting is done through a looping train with mixed wagons content.
I was told trains would magically improve UPS. Lies! Deception!

Here is a completely not optimized design. I'll be the average Joe, the control sample. I just wanted to see how bad my normal patterns would perform compared to the other solutions...
Full belt, no bot, no train or anything. GCs are made in a 12 beacon grid design, the rest is just normal smelting ...