TL;DR
Make Stops in the Train depend on specific dependencies in the train.What ?
Imagine a base where you have a trainstop only to refill gas on your trains. I though it where cool to have a only stop there if you have "more than X units cargo" or "less than Y units fuel" or something.Why ?
It would lower the fuel-consumption from trains. 'cause very far away trains doesnt need to come the long way into your base just to fill up every turn.Also it potentially make trainnetworks some less complex, or even more complex. I cant imagine for now.