Bulk train loader/unloader with buffer.
Mods introducing new content into the game.
Augmented or new ways of transporting materials - belts, inserters, pipes!
Can you make the loaders and unloaders be controllable with circuits?
They are already controllable with circuits:
Sending a BRL the special "Disable rail loader" signal will stop the BRL from loading/unloading a cargo wagon. Due to their speed, you are likely to load or unload a few more items than expected.
You're right, I missed that. I guess I was looking for an enable condition just like inserters have.
I could probably do that now in a GUI, but when I started the mod it wasn’t possible to show an inventory and inserter controls at the same time.
+1