Still haven’t seen anything on the new 377 addition. But since we have so many layers and existing stations, why not add that route? Great little route that.
It would probably be better as a branch of the North London Line route as the West London Line, including the Class 378. Although at this time I rather see plenty of other routes than another part of the London Overground network to be honest. Hopefully the Brighton Main Line can be remastered at some stage so we can at least get the Clapham Junction to East Croydon segment operated with the correct train type.