TL;DR
The stacksize is a vital information in many Traindistribution solutions, but we still have to set it manually.What ?
With the new combinators we will have the possibility to set blueprints so we don't have to setup our stations manually. When we now have some blueprint to calculate the amount of trains that we can fill we still need to either set the stacksize for each station, or calculate how much a full train will take.This could be improved if we had a "get stacksize of Item" function.
iron ore * stacksize = 50
iron plates * stacksize =100
Low density structures * stacksize = 10
Why ?
With this we could automate this part of the station setup to blueprintitem * stacksize * 40 * traincars = items per full train.I also used the stacksize in space exploration to calculate how many empty slots were left before shooting more stuff into orbit.