Oh …. And I forgot.
Store old trains
I would like to see old unused trains and wagons of little or no value to be stored on sidings to rust. I saw the buffer stop “loco shed” mod, which is a nice way of having building to create and delete new trains without forcing us to use many loco sheds.
Maybe use something like the way points where trains can sit idle or buy and sell.
You could then have quantities of wagons sit without locos, like in the real world.