Too late to rebrand "mining" to "network security" or "transaction validation". That would go into people's "good" mental category.
You know, I actually REALLY like this. In the future when I talk to the uninformed about this I'm just going to start telling them I validate transactions on the Ethereum network. It's far more descriptive, carries a positive connotation and it sounds way cooler.
-TBT
This is exactly how I tell people what I do that do not understand mining. Once I say that to them its like a light bulb goes off and they get it that much faster.