Am I the only one that enjoys mixing fluids?
When you fuck something up, you have to purge the pipes (I usually pump it out). Its a very simple and straight-forward mechanic, with parallels to conveyor belts with bad items on them. Being able to manually purge pipes is the only break in this ...

This is the first FFF I've thoroughly disagreed with.

Please don't simplify.

Complexity is what makes factorio what it is: a constant balance between build time, optimality/efficiency, and scalability. New players shouldn't be able to think for 2 minutes and work out the perfect factory design.
I ...

I like this direction.

Looking at the Production vs Science tech trees made me realise though: there needs to be a strong visual distinction between the items in one tree vs the items in both trees. A quick glance make me think "oh nukes! Much more useful than robots, I'll research purple first ...

I understand it could be a serious computational issue, but why not have robots physically collide with each other?
Overuse of robots becomes difficult, but could be managed with good design of flight paths (up to a point, easily controlled with payload capacity).
I find the current overlaying of ...