I meant the lower yields being disabled or well controlling the surface yields. Currently how you have it the above surface yields dont change when set to railworld. Meaning you have to expand way more often and WAY further out in order to keep a steady flow of resources. Going underground is a solution, but with how often one needs to change spots and how far you have to travel, its not viable to go deeper until you get further out or a stable enough throughput. As by the time you get deeper patches setup in full you'd need to move on to keep up throughput since most the surface ores will have shrunk and reduced throughput. Which becomes problem when this involves all ores.
EDIT: don't know how to strike this, but noticed that you adjusted the starting patches which may have been the issue i was talking about abovr
As for the other challenges, they help balance out using the underground. Without them its free stone and easy space. On void block for example, the moment i got the underground i quickly increased my land space by 1000 fold, and would have doubled the space if i had not left challenges on and needed to worry about pollution. Then the fact i had access to ores meant i could just ignore the void block's challenge all together.
Without challenges you can just place your entire base underground and never worry about biters outside of possibly surface mining posts, which once you hit oil are trivial to defend.
Which is why i suggested letting each challenge be its own toggles, so people can pick and choose what they want based on what their playing. Could even split the ore challenge into 2 toggles. one being the forced yield numbers, and the second being having ore underground at all.