The goal of this suggestion is to obfuscate the military unit counts of other nations, consequently introducing additional complexity to decision making at the individual nation level and at the alliance level, and further improving the importance and interest of intelligence gathering within the game.
Nation profiles no longer indicate the actual number of soldiers, tanks, aircraft, ships, missiles or nukes that a nation has, but instead are listed as Unknown in the same way that spies are. Nations are unable to see the improvements of other nations' cities or their projects.
Add an additional project, Satellite Surveillance. Satellite Surveillance allows the nation to see other nations' improvements and projects.
If a nation has Satellite Surveillance, when viewing other nations, instead of seeing Unknown as the unit count, they will see the maximal unit count the nation could have based on the corresponding improvements the nation has. For example if a nation has a total of 5 barracks, you would see max 15,000 on their nation profile instead of the exact number they actually have.
Add a nation setting to determine who the nation shares its military count information with; no one, everyone, alliance members, alliance government by tier (possibly allow setting this differently for each unit type, including spies).
Military counts should not be filled in automatically in factbooks.
Remove military units from nation score calculation.
Nations should not be omniscient. To my understanding, in the real world many nations' military capabilities are known due to publicly shared information. For example in Australia the ADF publishes reports outlining the number of personnel employed in various military positions, whereas unit counts for North Korea are estimated based on various intelligence sources such as satellite surveillance, border reports, public military parades and spy operations. This change helps simulate the gathering of information about nations through various methods, such as the Satellite Surveillance project, espionage operations, information revealed directly through warfare, and a nation's prideful bragging via its factbook (a kind of equivalence to military parades?).
The game should not make the choice for us in disclosing unit counts publicly, it should be left to individual rulers to decide.
This change would improve the importance of 'gather intelligence' espionage operations.
This change introduces an additional 'risk vs reward' assessment for individual nations to make in determining how they run their nation. A nation may consider maintaining a smaller standing army to save money on expenses while keeping the corresponding improvements to feign strength, but the risk of course is they will be more easily defeated in a raid or war. It permits a little more diversity in approach to individual nation defence, or even an alliance's general defensive strategy; prioritise return from taxes or military readiness.
As nations' military unit counts would not be easily observed and nation scores would not bounce around due to military unit counts, it would further enhance the importance of good inter-alliance relations and intelligence gathering in order for alliances to remain informed and prepared for wars. Instead of simply looking at a screen outlining an alliance's military growth as an indicator of military preparation for war, it may be necessary to be more observant of market trades for war time resources, to conduct spy operations, or even plant moles in other alliances or buy information from informants; all offering good provocations for war as well as making intelligence a more interesting and diverse aspect of gameplay.
While small nations without the Satellite Surveillance project will be blind to the potential military capabilities of other nations, they will likely be member to an alliance that will have members with the Satellite Surveillance project who can share information with them. Although minor, this is another way in which these changes may encourage improved communication and teamwork for information sharing within alliances.
Obvious point of serious contention:
Suggesting a change to the way nation scores are calculated is obviously a major point for consideration. I personally am not sure I understand why military units should affect a nation's score. It seems to me a nation's score should be based on factors such as infrastructure, cities, land, population and improvements. If two nations are identically developed, they should be equally scored, regardless of the decisions they've made about military investments. This point is also necessary in order to properly realise the benefits of this suggestion. If the changes were made without removing military units from nation score calculations, the effect would simply be that the specific types of military units a nation has, won't be obvious. Military growth at the individual and alliance level will still be observable and potentially indicative of preparation for war, nullifying the more interesting potential benefits of the proposal.