Respectfully, I think you are missing the point. Think of the risk/reward ratio. No matter how low the reward is for the pirate, the ratio is still lower then that of a trader. There is little to no risk for the pirate and, especially, well heeled killer. Traders will continue to migrate out of the open until the ratio equalizes.
Look at some other threads we had on safety balance between systems and expected returns. Right now there is nothing in the game that dissuades mindless shooting of the traders. I fly a well defended Python and have never flown without shields. I can hold myself in combat, and contrary to the OPs statistical claims, rarely take damage to the hull in NPC interactions (usually when I fly my new ship in its first combat and still figuring out how it works best), I just do not like the idea of having to run into an idiot who is going to shoot me because he's bored. Piracy and killing should be made a choice with consequences - you cannot show your face outside of anarchy systems if you are a killer. Conversely, if I'm a trader, I should expect nothing less but a fight if I decide to show up in an anarchy section.
I'm not sure the risk/reward balance is that far off what it should be though. How I define risk in this game is how likely a given situation will result in me losing not what I have right now, but the threat of losing the ability to maintain what I have or gain anything further. This equates to dying often enough that insurance starts to become a concern pushing you towards immediate danger of bankruptcy, followed by the risk of bankruptcy itself.
Now if we look at the various careers from this point of view, we can back-of-the-envelope guesstimate their risk to reward ratios. Start with the obvious because I won't delve into them all:
Trading:
-Primary motivation is income.
-Secondary motivation is fun though roleplay and co-operation, competition or conflict with other players.
-Main threats to the primary motivation are pilot error, followed by wanton murder and piracy. Given the low probability of encountering a hostile ship on the average milk run, the profit margins here are the highest in the game. Given the size of the ships and value of cargo needed for this profit margin, the rate at which a string of bad luck will push you towards bankruptcy is also the highest in the game.
-Low entry fee, high income scale once you start.
-Actual risk of bankruptcy or threat thereof is low, given the infrequent nature of hostile attacks, how few of them are likely to result in death, and the amount of money gained in between successful attacks offsets any loss for all but the most unlucky, unskilled or inattentive.
Low risk, high reward
Piracy:
-Primary motivation is fun through RP and conflict with other players.
-Secondary motivation is income.
-High entry fee for a combat-worthy ship that can still hold cargo. No income scaling, limited by cargo scooping mechanic.
-Income is possibly the lowest in the game due to difficulty finding valuable targets that will meet your demands or be unable to escape without dying. Not to mention being unable to ever scoop enough booty to come close to what that trader will make in a single run.
-Every outing comes with the risk you won't return at all due to police, bounty hunters, and targets that can defend themselves.
-Risk of bankruptcy is very high without taking up a different career for supplementary income to cover munitions, repairs, ship upgrades and insurance.
High risk, low reward
Bounty hunting:
-Primary motivation is fun through combat with either players or NPCs.
-Secondary motivation is income.
-Probably the second best way to make money if you pick your targets.
-Low to middling entry fee, reasonable income scaling as you get equipment to take on bigger threats.
-Risk of bankruptcy is low with exceptions for new players and ships with high operational costs (anything above the Cobra).
Average risk, average reward
Murderous psychopathy:
-Primary motivation is fun through conflict with other players. This is different from griefing.
-No income.
-Threat of bankruptcy is nonexistant as this is either done with free sidewinders or a limitless bank account.
No risk, high reward
And so on and so forth for mining, exploration, etc.
So my conclusion is that every gameplay style has its own inherent risks and rewards as a result of interaction with the others, and that these are all roughly in line with the figures they should be for those actions, with a few more notable exceptions like wanton murder, which everyone agrees needs more risk to balance its reward. Persistent reputation hits and an increase in the difficulty of removing wanted status and its negative effects is the right way to go, and for every other career it's just a matter of fine tuning the numbers.
What I want to say in closing is that we should all just cool our heels and not propose any major rocking of the proverbative boat, major feature changes that vastly impact large parts of the playerbase for the benefit of the few are best avoided in favour of minor, measured responses to emergent problems. We're going in the right direction so let's not make any large course changes, we'll only end up overshooting and have to double back to the station. Can you dig it?