So, I had a thought in the shower today about how we could go about implementing aircraft that, as of now, are on the drawing board (which includes but is not limited to the 737MAX/A320neo, 787-10, 777X, etc, etc). Essentially, it would work in a similar fashion to the randomly generated launch date for aircraft in game. Manufacturers promise that Aircraft X will have a 5% fuel burn advantage over Aircraft Y, as well as a 10% range advantage. Now, similarly to how the system randomly generates a launch date for an aircraft in game, the game would also go about generating a random set of performance characteristics for a proposed aircraft, with an X% margin of error in either direction (ie: if Manufacturer A promises an X% reduction in fuel burn vs current aircraft, the system would generate a fuel flow number within Y% of X.).
Just a thought I had, curious to see what the plebeians have to say about it.