Crossfire mod use dynamic economy - trading routes for normal commodities changes daily at server restart. If you do not like ask other players (this actually is very good idea … ask), then the best what you can do is use one your character for exploration (at least Sirius space) and have on this character purchased most lucrative commodities. With this you will see that trading in Crossfire space have some order which is unnoticeable on first look. (could be good idea check CF wiki on swat-portal for commodities which need only 1/2 and 1 cargo space)