For a Class

Here is why this is so hard for me to rate any of them:

Openness: While its important to me that heroes are willing to adapt, oftentimes heroes are simply those who happen to be on the percieved side of justice but are those who would likely never falter from their path. So they are conservative about their liberal ideas.
Conscientiousness: While its good to emulate the trustworthy, ultimately how trustworthy someone is is usually a result of how much they paid the media and/or how good their friends were at the time. When looking at historical heroes or even those of the modern age, unless you knew them personally its very hard to use this as a scale...but if something was leaked that they were, in fact, untrustworthy...but trustworthy doesn't mean honest. It means they can be trusted. Which isn't necessarily all that important for those heroes who stand against the system without many followers--they are likely untrusted by the system itself.
Agreeableness: Again, this is just so damn subjective but I think this is the one I would always rate last. Ultimately no one cares how friendly you are if you accomplish great things. Unless, of course, you are a social leader--i.e. a politician/diplomat like Benjamin Franklin or a social leader/movement leader like Martin Luther King Jr. In both those cases, friendliness is important. But if your someone like Tesla who fought against adversity but was largely a social disaster...there is something to be said about those who can succeed without this trait. Or in spite of it.
Extraversion: Its hard not to put this at the same level as Agreeableness. Not because they are the same thing. But because its hard to find many heroes who weren't either both or neither. They tend to play off each other.
Neuroticism: I want to just say that Crazy people can't be heroes. I mean: if they aren't mentally stable how can the mentally sound use them as examples without themselves acting crazy? Your not a hero if you run into a burning building and save someone because you honestly and firmly believe that fire won't hurt you and if you don't rescue the girl the angry fish god will drown you in your sleep with your own saliva. Which makes this VERY important on the list--how sane someone is is relevant to whether or not they can be heroes.