As a loco DLC for NYC-Trenton it won't include the ex-Metroliner cab-car since that is being folded into the main route, I think that's a good thing but it also means such a pack is lacking some extra rolling stock. If the SW-1000R ever returns to TSW3 it would be really good to see that taken advantage of as an opportunity to add some of the unique rolling stock Amtrak uses on its long distance services including the Viewliner baggage cars, sleeper cars (for the first time in TSW), and long distance Amfleets. NY-Trenton (as part of the NYC to DC) is the busiest area in terms of having multiple distinct long distance services that run down the line and stop at stations on the route, such as the Crescent, and the Silver Services meaning that this is where such new coaches would see the most use. From a gameplay perspective this would be workable as the long distance services are some which see the most switching.
You know, having actual photos help.... SW1000R Amfleet II Viewliner Baggage Viewliner Sleeper Viewliner Diner
Excellent idea and why not also make them in the following railroads CSX Norfolk Southern Canadian National and Burlington Northern Santa Fe they also owned them basically a livery pack including the Amtrak which is the original. Here's a BNSF Version doing switching job. UK Shunting German speaking parts of Europe DB SBB Rangieren ÖBB Verschrub