Why are we attributing risk only to human opposition? Yes, humans are sneakier, and capable of more than NPCs, that makes them a tougher opponent, which is admittedly higher risk, but just because NPCs don't pack the same punch doesn't mean there isn't risk involved; I can choose to hunt in a shieldless T9 with one laser, even vs. NPCs that's riskier than a well built FdL.
I can mitigate my risks vs. humans in multiple ways just as I can against NPCs; I can unlock new ships, get better engineering or modules, earn more credits to pay for it all, and all the while learn how to fly better. Is choosing to fly a lower tier ship any different to the risk presented when that's the best ship you've got access to due to progress in the game?
Risk is risk, mitigation is mitigation, and choosing to do certain things to raise or lower exposure to the risk is the same regardless of the presented threat. This is why actual risk is such an important thing for the equation. If we want risk based rewards it must factor in all risk, and all mitigations, not just one facet. PvP is high on the risk scale, but PvE, and the various levels of ship/NPC capability, make up the lower echelons of that scale.