Steam Workshop may be what you are looking for.
As of today, fifteen additional scenarios for the Springfield Line route DLC can be downloaded there, with a total playtime of well over ten hours!
I have created a Workshop Collection for all the Springfield Line scenarios so that you can find them all in one place. The collection includes a wide variety of scenarios, covering almost everything from yard switching to high speed passenger running. It features scenarios by authors StevenJam, RolandBP, tompallen, Joshua Harkness and me.
Here is the link to the Workshop Collection:
Enjoy the new scenarios for the Springfield Line!