Scenic line that hosts amtrak's coast starlight, pacific surfliner, and a variety of metrolink trains. It has a length of 70.9 miles with 12 stations, and is mostly suburban, with farm fields further into the route and the rocky santa susana pass about mid way through. 3 stations for this line have already been done on the Antelope Valley line including Los angeles, Glendale, and Burbank. This route could include a Metrolink F59PHR locomotive to supplement the MP36 and the F125 already ingame.
And of course, we need the Surfliner SC44 Charger w/ Superliner and PS Cars/Cab Cars and the ALC-42, P42DC Genesis, or P32-8BWH "Pepsi Can" for the Coast Starlight. The Amtrak Dash 8s are commonly used on the CS or for yard duties, although they no longer wear the classic Phase 3 "Pepsi Can" livery. I'm still hoping for the ALC-42 in game.