6. Economies of density: Allowing new airlines to access markets will dilute the market for incumbent carriers. Thus Lufthansa will get less traffic through its Frankfurt hub, and it will lose some economies of density. Thus there would be a small negative to opening up the Berlin market to Emirate.
9. General equilibrium effects: It is not clear how it would affect the assessment of the Berlin case
10. Impacts on greenhouse gas emissions: The berlin route will reduce their emission from other routes. The net effect also depends on how efficient the airlines are in cutting back on emission.