I think Aerobiz can be a good start as a "base" to work on, but more I play with "AirwaySim" and a bit with "Airline Empires", I think that these two are (at the moment, I haven't still received "Airline 7" 
) the best on the market today.
Do you want at least 300 airports? I want, at least, 3000 airports (possibly more)
Ok, I know it can be a "little" difficult, but, if you plan to do a game that it isn't only international flights, 300 is a small number, I think.
Today, only in Italy there are 42 (as AirwaySim said) from local to international airports... and this is a conservative number! For example, I live in Reggio Emilia, and there is a local airport with a 1400 mt. runway!
If you really want a complete (totally!) list of possible airports, you have to see this game (http://www.myairline.it/): it's, sadly, an Italian language game, but they have done a huge job to find ALL the possible airports in the world, and also for the models of airplanes selled between 1980 and 2013.
I think that, thinking about the game, you can simply do a "general" behaviour, demand and destination routes for local airports, and "hand" modify only the 500-1000 largest airports in the world cool
As we said (I and MrX) a game when you can choose to be a local, regional, national and international company (or all) can be longer to code, but surely the BEST on the market, because it doesn't exist a game like this, today.
Ok, for the number of possible IA and world map type/style, it seems charming
I agree also for the economy part.
I VERY agree also for the data taken/good as in AirwaySim, but really don't forget "MyAirline" (I can help with it, if you need)
I will also look to a method to create only-transport company (goods) or let the user to create a company that can do pax and good
Also, it can be a great idea to have airplanes not used for common routes (airplanes with less than 5-10 passenger cargo), but as tourism, little cargo or "special" airplanes (we can think about what, for now I have this "vision").
Ok, I have said enough (and I understand if something of this list will not be present in the game ).
) the best on the market today.Do you want at least 300 airports? I want, at least, 3000 airports (possibly more)
Ok, I know it can be a "little" difficult, but, if you plan to do a game that it isn't only international flights, 300 is a small number, I think.
Today, only in Italy there are 42 (as AirwaySim said) from local to international airports... and this is a conservative number! For example, I live in Reggio Emilia, and there is a local airport with a 1400 mt. runway!
If you really want a complete (totally!) list of possible airports, you have to see this game (http://www.myairline.it/): it's, sadly, an Italian language game, but they have done a huge job to find ALL the possible airports in the world, and also for the models of airplanes selled between 1980 and 2013.
I think that, thinking about the game, you can simply do a "general" behaviour, demand and destination routes for local airports, and "hand" modify only the 500-1000 largest airports in the world cool
As we said (I and MrX) a game when you can choose to be a local, regional, national and international company (or all) can be longer to code, but surely the BEST on the market, because it doesn't exist a game like this, today.
Ok, for the number of possible IA and world map type/style, it seems charming
I agree also for the economy part.
I VERY agree also for the data taken/good as in AirwaySim, but really don't forget "MyAirline" (I can help with it, if you need)
I will also look to a method to create only-transport company (goods) or let the user to create a company that can do pax and good
Also, it can be a great idea to have airplanes not used for common routes (airplanes with less than 5-10 passenger cargo), but as tourism, little cargo or "special" airplanes (we can think about what, for now I have this "vision").
Ok, I have said enough (and I understand if something of this list will not be present in the game
).