I agree. My basic story for the route is that in the 1970s, the American National Railroad Corporation, an alliance between many different railroad companies, was formed as a conglomeration of most passenger and some freight lines across the United States. American National found themselves with hundreds of freight and passenger locomotives, and repainted most of them into its famous red, white and blue colors. The route, of course, aims to simulate the early days of American National, both its passenger and its freight operations, in the summer of 1973.
Inspired by Amtrak and the Bangor and Aroostook railroad, American National adopted this simple paint scheme for most of its fleet, especially passenger trains, though some freight trains had this livery too. Its only other livery was a simple all-black livery with white "American National" text.
That's all I've got for now, really, but there's a lot more work to do yet.