One of the things I like about Black Powder is that the authors stated their preference for games based on historical scenarios, rather than a perfectly balanced game based on point systems. I therefore find it surprising that the rules state (on page 10) that most units should be of a standard size, with only exceptional units being large, small or tiny.
Historically such a structure during the Napoleonic era would probably have only applied to British armies, due to their deploying single battalions overseas, initially at strengths of 1,000 to 1,200, but rapidly decreasing by attrition to an average of some 600, and when reduced below 300 amalgamated into pairs as provisional battalions. Only the Guards and some Light Infantry managed to maintain their large size. Most of Wellington's battles had a few large battalions (those recently arrived plus Guards, 43rd and 52nd LI), most of standard size and a few small.
The French however deployed in multi-battalion regiments, most of which fielded 4 battalions, nominally of 840 men each, early in any particular campaign. As attrition set in the French reduced the number of battalions per regiment, so most French battalions were of a similar size of some 500 to 600.
The Austrians however fielded armies most of which comprised line Regiments of 2 or 3 very large battalions of some 1,200 men and were not normally in the campaign long enough for much attrition to occur. A historically correct Austrian army would not conform to the Black Powder large battalions rule. I would guess that the reason for this rule is that an army comprised mainly or entirely of large battalions would be too powerful. In my view this is because Black Powder does not have any of the historically accurate penalties for large units, which is that they were slow to change formation and slow to advance in line (the latter because the longer line hit more minor obstacles, thus requiring more frequent disruption of the line with the obstacle avoidance drill used by all armies). To avoid this British large units often divided into two wings, and Austrian large units into 3 divisions.
I would prefer to allow historically correct armies but have proper penalties for large units, which I would suggest should be some form of movement penalty when in line and slower formation changing (or the need for a better dice roll on changing formation) for large units.
It is interesting that Black Powder currently has disorder only arising from shooting and hand to hand fighting, not from movement. Hail Caesar however has no disorder from shooting or hand to hand fighting, but only from movement interpenetration or break tests. I do not know the logic for this variation, but historically the major cause of disorder in any era was from movement, particularly if it was over broken ground or too fast for the formation the unit was in, compared to their training.
Rod

