If you want to stock, it's gonna cost you ressources, space and logistic, because I personnally believe you're supposed to run your factory smoothly, with small chest for buffers...
That's also push us to make bigger trainstation with space to handle huge stock, so wider trainstation like a tile or 2 wide for a dock, more realistic too.
OpenTTD mod:
![Image](https://wiki.openttd.org/images/c/cf/Newgrfwayp.png)
And so you need special giant inserter to unload a train, if we make a wagon bigger capacity:
And why not a way to stock things is to use wagons:
![Image](http://cdn.c.photoshelter.com/img-get2/I0000sY2IWh8nVJ4/fit=1000x750/Railroad-Freight-Yard-at-Dusk.jpg)