If you go to view world before joining you can see the top airlines, airports and bases. Airports like LHR, ORD, ATL, CDG, FRA etc will always have stiff competition. You will not be able to see the route structure out of each airports untill you have joined the world. Again routes frome the biggest airports to the closest destinations and to the biggest airports withing reach of the starter plane and slightly bigger will have competition already established.
If after you have joined you find that the airport of your choice is not to your liking you can email staff for a reset and try somewhere else.
