Hi All, Does anyone have tricks to get ore freighters to carry more ore or just in general be more efficient?

I have a spiral down to grab ore and bring it up top. I have mass storage with thousands of ore at the bottom, room for thousands of ore at the top, and maybe 20 large ore freighters assigned to the station up top. I read somewhere that large ore freighters carry 500 ore. But in practice, mostly they'll roll up and grab what looks like 20 or 30 ore or maybe 100 ore and then turn around and leave. Also, if they roll up while another cart is using the station, they just turn around and leave with no ore. I'll have all 20 ore freighters going back and forth at all times, but they still never carry more than about 1,000 ore between them. Since it takes a long time to get from the surface down to the nickel I'm trying to move, it slows production way down.

I tried switching the mode on the stations at the bottom to wait to load all, but that appears broken. They'll wait and load 500 ore but then they'll never leave at the end. They're stuck there permanently.

Any other ideas?