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Historical Industrial Growth

I've made some changes to how industry is initially distributed and grows over time.

These changes are a nod at historical realism but I've tried to keep the abstractions at roughly the same level as the vanilla game. There's no new things to build or new resources to keep track of.

1. Civilian factory construction speed is now reduced the more civilian factories you have.
   
2. Military factory construction speed is now reduced by how much of your total industry is made up of military factories.
   
3. Military and civilian factories have been redistributed across countries to account for my subjective view of industrial potential. The major powers are significantly more major. Minor powers are significantly more minor. Resources are also amended (using the resources from Professor's mod)
   
4. The generic focus tree now only provides one military and one civilian factory.
   
5. The number of factories you receive from occupations is massively reduced. Resource extraction and manpower from occupied territory is unchanged.
   
6. The number of building slots per state is now 72 globally (with the exception of like wastelands and small islands). If anything it should be higher but I couldn't find any mods on the workshop to show more than that on the state screen

Increasing civilian factory cost
In HOI4, developed economies have higher growth rates than less-developed ones.
In reality this isn't the case. As a less-developed country it's very easy to take the conceptual, technical, or scientific developments of more developed countries and apply them locally. 
 
By comparison for highly-developed countries to come up with new innovations costs significant time and money, and many of these may never pan out (the canonical example for this effect is pharmaceutical development, but many technical and manufacturing processes are the same). 

I've tried to apply this by giving countries a small buff to their initial factory building, and then penalties that get more severe as your economy grows as follows: 
 

Increasing marginal military factory cost
In HOI4, there is no marginal cost to building military factories beyond the resources used to build materiel (e.g., if you have no more steel and no civilian factories to purchase it with then there's no point building more military factories). 
 
In reality there are finite stocks of things like machine tools and skilled workers, and the more factories you have the fewer of these are available for your next factory. 
 
The greater your peacetime industrial base, the less impact this has - you have to train fewer people for new military industrial employment, for example. 
 
To try to model this I've added a construction speed debuff that maps on the to your country's ratio of civilian to military factories. 

 
 
Redistribution of factories
The Irish rising up and taking over the world (or the Mapuche, or the Finns, or a resurgent Austria-Hungary, etc., etc.) is great for YouTubers but requires a distribution of economic, doctrinal and technological power that isn't necessarily realistic.

To try to amend this I regenerated the industrial capacity of all the states in the game. I've tried to use as best I can per-capital industrialisation data from Paul Bairoch, per-capita GDP data from Adam Tooze and GDP data from Mark Harrison (among some other little sources).

Lots of this is 1938 data, but I think the important part is the relative capacity of each nation rather than the precise numbers. If there's some big '36 to '38 outlier to account for (that isn't covered by, e.g., focuses) let me know.

I've included the python script I used to generate the new distribution. It uses a level of per-capita industrialisation, military spending as a percentage of GDP, and state population to generate new distributions across countries. Please feel free to tinker with it!

There's absolutely no way the distribution is correct state-by-state, but country-by-country I think it feels closer to reality. 

 
Occupied industry
From my understanding while much of occupied Europe was exploited ruthlessly for raw resources and for forced labour, industrial output collapsed across the board (and were actively competing for limited coal and iron against overlord-based companies).

As such the number of factories granted during an occupation is now only that level given as you raise compliance or through occupation laws.
 
Geographic expansion
I think no country on the planet hit a geographic limit on their economic activity. We still haven't. A landmass the size of New Zealand could hold the entire world's population if it had the density of Manhattan!

This is indebted to and uses a little of the work from the following:
https://steamproxy.net/workshop/filedetails/?id=3207099828
https://steamproxy.net/sharedfiles/filedetails/?id=700308938