I haven't been around much in the last year but last I spoke with Sami, demand will be low unless evidence of real world traffic exists. Demand in Airwaysim is mainly based on real world available seats.
Istanbul to Izmir is the busiest air route in Europe, but has 140 seats in AWS.
LAX-SFO/OAK carries 6.3million pax a year but in AWS demand is less than 500 a day. (350k seats/month for LAX-SFO)
Seoul-Jeju has 840k seats/month and carried 10 million passengers in 2012; Demand in AWS is about 800/day. In fact, in terms of passengers transported, Seoul-Jeju is the world's busiest travel route. Just go to flightaware.com and look up the # of flights between the two cities.
There are many more city pairs than the ones i listed above. So there is plenty of evidence real world traffic exists for certain routes; they just never get implemented.