Train Sim World 3 doesn't allow for modding or user created routes. This makes it unappealing to many of us, for it doesn't have that long term loyalty that other old time simulators have. Still I find TSW to be appealing in that you can work the trains on foot. The 8 key (along with the 3 camera) as usual may be used as the conductor to ride the back of trains, get off and cut cars. The coupler action in TSW is what originally draw me to it. Then I find that the 3D modeling of trains and objects, particularly trees, is the best out there.
Here I explain how to use the pretty lame scenario planner and how to overcome some of its limitations.
TSW3 : Scenario Planner Tips!
https://www.youtube.com/watch?v=PHJODsCWA8g
AND here is a bonus eye candy video
Let it Snow! Downhill on the Clinchfield
https://www.youtube.com/watch?v=8qsNHErUtHY