Weather has a huge real world impact on aviation. What good is a hub, terminals, and billions in aircraft... If a major airport is shut down, or reduced to a weather category that renders it inefficient? Chicago O'hare (KORD) is a victim of this commonly in the winter; making it a great example. A huge airport that can be brought to a grinding halt for days. This would introduce a new aspect of efficiency to the sim. Real world/real time data would be great. Simulated wx would work just fine. It would merely add another layer to the sim.
To implement wx in the current system would be easy. Add conditions at airports. Assign wx catagories. Create modifiers for the categories.(Basically, weather penalty). Apply modifiers to rate of flights on route. Arriving or departing an airport who is atmospherically affect will reduce the amount of flights; If Arr/Dep airport is in closed condition, no income will be earned until the airport has re-opened.
This would be a very simple wx system. Again though, it would add a new layer of realism. In real life the effects of wx are much more drastic. Turbulence and icing can cause delays when the aircraft needs to be routed around it. Delays and closures on the ground. Visibility has a lot to do with the rate at which planes can land. Morning fog, is enough to reduce visibility conditions to a slow category.Just a suggestion. Looking at some of the things coming down the road, the realism seems to be going in the right direction. I must say, I am truly excited about cargo. ^^