Cajon Pass features 3 stations on it, all, and with how the Class 700 is being added to the SEHS route, it seems now is the time for DLC compatible with the base add-ons. This is why I believe the Southwest Chief add-on should be released for Cajon Pass, featuring the eponymous P42DC locomotive and bilevel Superliner cars. It would stop at Barstow, Victorville, and San Bernardino stations already in the route (which hint to a DLC of this kind), adding a new level of operations on the line. It would be the debut of General Electric’s Genesis P42DC from the ‘90s, which could make a useful asset for later Amtrak (and even Via Rail) routes, and layer onto the existing NEC routes. The classic ‘70s Superliner cars based on the AT&SF’s Hi-Level cars would also make a good addition to the fleet.
The SW Chief arrives in Barstow early in the morning when it's still dark. The Amtrak P42DC is a must have for TSW3, but not on Cajon. The engine could also be seen on HSC and Sand Patch, but we really need a dedicated passenger route for the P42DC (perhaps the Pacific Surfliner).
This might be suited for a upgraded Northeast Corridor Boston Providence because it will run there whenever they have to perform late night power maintenance repairs which causes trains 65-67 the night owl to be on diesel power instead of ACS-64. Matching coaches are Viewliner II Sleeper Baggage car Capitol Limited and Southwest Chief Superliner II
You run into the same issue as on the NEC as you do on Cajon, it's a late night train with very little AI traffic. It's wasted even more so on the NEC as they don't shut the power down all that often for that extended of a time. They're more likely to just annul the trains as the work gets done than throw diesel power on the electrified corridor. The Harlem Line would be a good place to introduce the Genesis-series into TSW, granted it would be the P32AC-DM version of the unit. It would add some real-life variety in between the silver blurs of the M3s and 7s, and would at least get a Genesis model into the game. From there theoretically it shouldn't be too hard for DTG to tweak a P32 asset into a P40 or P42 asset if a dedicated route for them were ever to materialize. Some minor exterior and interior differences, a couple sound tweaks, and changes to the power curve physics.
I find your input helpful and for the GE Genesis locomotive Amtrak also has P32AC-DMs that can run on the Hudson line if made. P32AC-DM Metro-North usually runs with Shoreliner I-IV which can then be modified to spawn a Comet I-IV from them.
Definitely agree, the P42DC and P32AC-DM should be recreated in TSW3 as it is one of America's famous diesel locomotives designed for passenger services. I am sure it will arrive at some point as it was developed for TSC so the devs have the reference material needed to create it.