It is the very lack of risk in solo that is causing the problem.
Trading should auto-regulate itself. The more expensive your ship and cargo, the more profit you can make. But the more danger, and risk, you face.
But the rarity of risk in solo has broken this balance. Providing huge profits at little risk. This had a knock on effect of making all the other careers seem under rewarded, hence the recent boosting.
At the end of the day, the game should be fun. Being repeatedly destroyed in what seem one-sided encounters is not going to be fun. But there are better ways to fix this than just removing these encounters entirely.
This is ! You do realise there is absolutely no difference in risk between the player who is in solo and the player who is in open but trading in areas not populated by the ganking jerks and not seeing other players? Why do you people not understand that? What's next, penalise the player who does his trading etc away from the core systems simply because the murderers and gankers can't easily find them out there or attempt to blockade trade routes? Auto-regulate, as you call it, trading that is done outside the core systems? Just goes to show that people like you STILL don't understand how this game works......