Hello!
I personally have not yet created my own world, however I am planning to do so in the next month or so.
I have however, played in a number of private worlds so far. I have picked up on the following:
1.) If you allow too little airlines to join, people are not interested and the world will be an 'easy' one to be in as there are not much competition then.
2.) Having too many airlines join (say 100+) then the competition gets crazy, especially if its a limited continent world i.e only Asia or Europe. I personally enjoy a full world
3.) The 'starting' aircraft I guess has got alot to do with it people making their choice to join or not, as well as the start up cash
4.) I don't know about other players, but I enjoy modern worlds which are not too long, I join worlds with a playtime of max 10 years. Reason being, if you have 500+ routes its a mission replacing all the aircraft once its reached its limit (in my case, I replace all aircraft once it reaches 3 years of age). Playing in a world which is not longer than 10 years, still allows for manageable fleet replacement
5.) The amount of focus cities you allow players to have has also probably got a small part in their decision to join. If you have a ridiculous amount set for local and international, I doubt alot of people will join. A fair combo such as 7/2 or 6/3 works out well, I'd say.
That's all I can think of at the moment. I'd be keen to join so let me know what you're ideas are for the world... Hope my input helped a bit.
