So, is military efficiency totally dependent on military spending? (I mean, besides DefCon levels, and training.) That is, if two countries have the same pay levels they will have the same MilEff?
Yes, thought the cost of salaries and maintenance/training are related to GDP/c.
If that is so, I would be curious to know how I might change that, because I think spending is only indirectly related. Cultural and doctrinal issues mean much more...
It is not something you can change, it is built that way. That is also why efficiency changes gradually over time since you can't change funding and see results next day.
...Conversly, if the Russians or Syrians had enough money to equal US military spending, they wouldn't produce a US quality army, for long standing reasons of doctrine and military culture...
Our take on it is that this is because a high efficiency T-72 is still a T-72. If Syria spent like the US and bought expensive equipment like the US does, the differences between the forces would be much less. While it is true that there are some nuance elements we've overlooked, they would be very difficult to model in a game so we left them out.
...But can you tell me how I might do these things anyway? What program I could use to convert the appropriate files to an editable format?
Not being a programmer I certainly couldn't tell you how to change the MilEff stuff, nor have we made our source code public. For the Campaign progression, there is a nextmap variable in the .GMC file and I believe a file with a "starting scenarios" list somewhere in the folders (been a while since I looked at any of that) but I don't know if George uses other coded elements to set the campaign, never needed to learn about that...