Instead of giving you the normal "you are a pilot, fly some routes and earn some money" routine, you are a contractor. Your choice of aircraft and your on time performance will go towards improving your reputation which will increase the number of passengers that want to fly with you. As you grow your passenger base at each airport you will want to buy larger aircraft to handle the loads.
What's nice about this model is it allows you to fly any aircraft. If you like the modern, fuel efficient, aircraft you will maximize your credit and reputation. If you like turboprops only then that's fine, too. If historical aircraft are your preference you can fly those too knowing that you will not be as fuel efficient as the modern aircraft and not as safe in the passengers eyes.
To join FSC send an email to abatflightsimenthusiasts.com (replace the at with @). Tell me where you want to start (ICAO) and you'll be given 1,000 credits to get started. If the aircraft you want is more than 1,000, tell me which aircraft you want and you will receive loan that must be paid back before you can purchase another aircraft.