RE: Why are unit sizes still different between Gold titles?
I cannot speak with any authority on this, however, I will throw in some currency on the matter. I echo the sentiments, and I think part the matter is the evolution of how the 4th company, or heavy weapons company, is treated. This has changed for many scenarios and games, particularly on the eastern front. Some scenarios, which I think it started with the alt scenarios, got rid of the heavy weapon company altogether. Therefore, battalions only had 3 companies instead of 4 listed. This was the first evolution that I noticed. The second one was the emergence of the 4th company again, but as a normal rifle company. This allowed the german player two units of combined infantrymen to help combat the large Russian infantry battalions that were not broken down to company level. I only noticed this configuration on the eastern front titles.
The heavy weapon company, in my view, is hard to accurately represent at the current scale of the pzc series. Thus its 'evolution' over time.
I'm sure this is only part of the story.