To disable the default traffic...
Go to the ...\Scenery\World\scenery\ folder. Find the default traffic file, trafficAircraft.bgl. Change the file name extension to something that FSX doesn't recognize, example; trafficAircraft.bgl.original. Or you can move the file to somewhere outside FSX for safe keeping. Note that either will remove all default traffic, airlines and ga.
If you want the default ga traffic there are a couple of options....
-Go here- http://www.flightsim2004-fanatics.com/uploads/DefaultGA/Def_GA_DL.htm
-and download the FSX GA Traffic file. Note, the bgl's are in FS9 format so you'll have to convert them as you did the WoAI files.
-If you used AI Flight Planner (AIFP) for your conversions, it's easy to use the program to compile a sub-set of the trafficAircraft.bgl that only has the ga traffic. Refer to section 6.7 of the AIFP help file.
At that time  the chief engineer was almost always the chief test pilot as well. That had the fortunate result of eliminating poor engineering early in aviation.