The underground belts can be scanned by holding another underground belt in hand and facing it to be an exit then you can just walk along the line to where you want to place your new entrance.

I also agree and propose fixing the problem by making the pickaxe just an upgrade that when researched improves mining speed rather than being a tool. May also want to look into calling the steel tools upgrade to explain why it speeds up all mining speeds.

Yes, being able to see what is built from an item could be very useful for setting up assembly lines just so you know what other factories will need to draw from it, so you can build in the space ahead of time rather then having to rip everything up latter meet the demand such as for electronic ...

Currently in Factorio weapons are switched between using q as a cycle key to switch weapons from left to right and skipping over weapons that have no ammo.

My new idea is to add a toggle key such a "C" to act as a switch between building mode where 1, 2, and 3 are selecting from the hot-bar to ...

Back to the need of a stone recipe.

What about adding stone slabs as a building requirement to the conveyor belt recipe and stone in the form of gravel to the train track recipe. The effect of doing this would convey to players that stone is like a road and wall material that is used to surround ...

What about letting them solve the tree problem.

Let the biters go around nearby forests and plant trees. This would fall into their need to protect the environment as well as make players consider keeping small bases of biters around to replant trees for them. This may also create a more symbiotic ...

Additional Events/Locations

-Robotic Camps (normally small lootable basses controlled by a neutral parties that are fully automated and running, may even show off some base design ideas)
-Corrupt Robotic Camps (similar to the above but larger and hostile to all biological entities aliens or players ...