You're doing it wrong, then. Roleplay when trading. Or don't trade. If you get bored while playing ANY role, it is not the fault of the development team or the administrators by default.
I have never bought a personal battleship because "a personal battleship" is something that within roleplay terms sounds retarded.
The diamond-niobium run in 4.84 would get you no more than 43 million credits per hour.
If you want more, you are broken, not the trade system.