I might have to spend some of the "railroad's" money and add some parallel sidings. It seems reasonable that not every time a car arrives at an industry it is immediately unloaded, or loaded. There simply must be ways to get the engine on the proper end of the consist so it, and its cars, can get on to the next customer. A poorlyl maintained (cheap) siding will cost something but pay for itself in customer satisfaction from shorter schedule times..
Many railroads do this by setting up small runaround sidings so a handful of cars can be pulled into the siding and the engine uncoupled, and sent to the back of the train to push the cars into the siding. There was an old single track line, that's now abandoned, that had this arrangement.