Well not knowing the terrain of Glacia, Spain, etc , I cannot make a suggestion or criticism, but probably more trees and other scenery would be more natural.
Basically I constantly use the "G" key to help identify the levels of terrain, and in this scenario, I used as many valleys as possible, but did not relinquish hills.
To compensate hills, I strictly used the DX Goods 0-6-0, until the Vitorio Emanuele II 4-6-0 came into availability.
The Duke and the Sterling have more speed, but do not have the power for the inclines.
Unlike my 1st attempt, I was able to get the Gold with a few years to spare. I did run into some Depressions which dragged down the Stock Purchase Power, but did not invest in any industry. There were intrmittent crashes, which totaled at least 6, cutting into the hauling profits, but had good commodity hauls during the Prosperty economy, and only had a couple Booming periods.
Although I don't really like to navigate thru mountainous terrains, the terrain of this scenario was durable, and there were enough valleys to compensate, even though some track routes were some what longer.
A great scenaio, and enjoyed the concept and challenges.