To me, the matter is simple. Going from A to B and back = boring, when it gives reasonable cash, then half that. When it brings little, I just maintain my chars on waht I loot/rob/capture/kill/mission-pay
Shooting(even NPCs) = fun when doesn't tae too long. I'm not talking about an absolute pwnzoring of thise NPCs (what they are made for anyway), but difficult to survive missions, that give hard pay. Killing 12 sabres in omega 15? sure... If they don't bounce around abd b/b into infinity. taking on 8 Osiris-class battleships? Either suicide or an infinity of gun strafes. And for what? Barely enough to restock ammo and cover the repair costs?
On another mod, missions were the main source of income. each NPC had a lil' something onboard, that cost horrendous money on a nearest battleship-base. These thingies (costing 150 000cr. there) made up more than half of the overall mission income. (base - from 200k to 960k) Then - a capship there cost a minimum of 800 mil. Setting up a fighter was nearly as expensive as on disco, but pimping it out needed much more... 10 mil a piece of equipment (best scanner, armor, shield, etc...) It worked. Haven't seen anyone but BIG clans flying capships there. The NPCs there didn't have the advanced AI of the disco ones, as such were quicker kills, but nevertheless, alone against the dozen of them, I had little chance of survival. They just had very good weaponry.
So to sum up, trade is fine as it is, boring enough to make me want to drop disco, profitable enough to make me stay.
Missions however have lost their initial goal - the primary source of a fighter pilot's income. Not enough gain for the effort.