I am not intimately familiar with all of the 'engines' or subroutines that go into a game. So, I will call this a part of the 'game engine function.'
Below is a quick, incomplete, illustration of the evolution aircraft units. Could the game engine re-create this and could it have an early war with few aircraft develop into the crowded skies of 1917 and 1918?
In the summer of 1915, the eindeckers appear. The French had started with Garros Morane L and had deflectors on the Morane N. The Brits flew these in 1 sqd and had their own FB-5 Gunbuses.
The name of the game throughout the war is get the recon and artillery types through. And the organization of the 3 airforces shifted a couple of times as airwarfare was further realized.
In the beginning, the eindeckers were singularly assigned to observation units with the exception of two being assigned to Boelcke and Immelmann in FA62. Often, pilots would go back and forth between the Fokkers and recon aircraft. In this time early C types are still flying escort.
At Verdun, the Germans set up battle flights which were a failure. You would also see aircraft like the Roland C.II flying as an escort fighter for the recon aircraft.
In Summer of 16, the single seaters are more or less concentrated in KEK, Kampfeinsitzerkommando units.
In October 16, this is take further as the Jastas are formed.
In January 17, the Flieger Abteilugn units are renumbered based on if the unit was recon or artillery.
With the introduction of the Nieuport 11 and the DH2 in early 1916, the British and French develop fighter squadrons. The British learn art of reconnaissance, at a cost, at the Somme. The French rule in Verdun.
The French make modifications to their units a couple of times further into the war. The British eventually form the RAF on 1 April 1918.