I lieu of the connections at Eastwick and Westham, you could put another crossover between the mains on the "viewing" side of the layout to accomplish your runaround for passenger trains. perhaps right in front of the Westham area is enough straight section clear of the bridge to do this.
As for the siding under the mountain, it looks too short to be of much use. If it is not long enough for most of your trains, I would eliminate it or lengthen it.
