Faster, larger inserters to reduce UPS/FPS issues. Modified for pymods. Based on Karoschel's Inserter Cranes.
6x2 and 3x2 cranes with hand stack size 250.
The problem is that their acceleration will completely disrupt the balance and make them too cheaty (overpowered). Their primary purpose, after all, is loading and unloading trains, while loaders are better suited for unloading onto belts... So I recommend using something like this:
Fair. I am a bit confused as to why altering the extension speed would cause it to become imbalanced though. It would still take just as long to swing, I think.
