Early game revamp
I think the game could relatively easy be enriched by expanding the early game. Perhaps having the player start with only one a few guys with shovels and pick-axes. They need to start very slow by mining out material, making bricks, smelting iron, etc. in smaller hand-operated "machines" in a pre-electrified era.
I believe much of the technical infrastructure already exist to expand the game in this direction. A person with a shovel/pick-axe is basically a vehicle/excavator with capacity of 1, and a crafting bench is just a very slow assembly machine with no ports.
The option to start with the dock, boat and some materials could still be there as an "advanced start" sort of option, and I think that the factories, trains, boats, etc. will eventually feel even more rewarding and cool if we knew we started with just one guy and our bare hands.