TL;DR
I am suggesting a different way to rotate the endpoint when building rails using ghost build mode.What ?
Currently when you hold shift to enable ghost build mode for rails, the only way to rotate the endpoint is to spam R. It can actually be kinda difficult to get the correct rotation first try so I often end up having to spam R at least one full rotation around to get the angle I was looking for.I suggest adding a feature which, when holding down R, draws circle around the cursor and locks the endpoint rail position in place. Then, when the user moves the cursor outside of the circle, the endpoint will rotate toward the cursor. Letting go of R will unlock the endpoint position and cause it to follow the cursor again like normal.
I suggested drawing a circle specifically because it allows the old behavior of spamming R to still work without any changes. Most people won't be moving the cursor around fast enough to move it outside of the circle for the brief period that R is pressed down. That way, we can have both features at once.
In some ways, this suggestion is also similar to the "new" way of building belts. When dragging belts, you can press R to make it rotate toward the cursor. The difference is that the belts will be rotated toward the cursor and then built immediately while the rails would only be rotated toward the cursor and then built only if you left click to place the planned ghost.
Please let me know if my description wasn't clear, I could make some concept images and stuff if needed
