You can easily edit yourself your ai traffic :
Fisrt you need Traffic tool
from Lee Swordy. It allows you to decompile and recompile FS AI Traffic. You can make a single AI Traffic File(compiled as .bgl) for your all AI Flight Plans or several(.bgl), one for each airline, or one for each geographic area.
A readme file is include with this wonderful freeware programm, explaining how to proceed.
Then, you'll need some basis aknowledge of how to edit an AI Flightplan.
It's quite simple but once again, you'll have to read...
Once again, you can edit manually the Flightplan.cfg or use a freeware program like AITM(AI Traffic Mover)
But i let professor Crazylegs teach you this second part of the process....