I enjoy the game quite a bit. There is a bit of interaction between the economics and the developing rail network. There is also a factor of trying to guide the location of different factory types to be more rational and fit in better with yours plans for your network. Basically if you leave the factories to be built by the private interests, they will often put up factories very far from their supply sources and markets. Building them yourself can be more efficient, but maybe you don’t have the money to do that at the time.
I agree it is mostly about thinking about how to build and develop an efficient network over time.