It would be cool if we got the addition of saving your consists into the game, and using them for the Scenario Creator and so we can spawn them in instead of having to redo them. It would be cool for doing roleplays like "NJT 40th Anniversary Train", it should also have the liveries included with them so it wouldnt be ruined. The Viewliners would be great for this too, I think you guys should add them soon since they are a crucial parts of Amtrak and doing On-Foot travels. I hope you consider this idea.
We do have something like that coming. It's called Formation Designer (I think Consist Creator is a better name). When it's released in the Winter Core Update*, you can create your own consists that can be used on Free Roam and Scenario Planner! *I am 95% sure it will be released in the Winter Core Update
