So when you start on a server after a wipe, you start at zero and you can do one tiny good thing and still be okay [for the mission's virtue requirement]?

No, you can do a few. It's a kind of sliding, exponential kind of curve. So as in real life, if you're a bad guy and you're known for being a bad guy, if you do something bad, it really doesn't make much of a dent, because you are known for being bad. But if you do something good, if you rat on someone, suddenly you're way back at the start. They don't think you're bad anymore. And it's the same if you're good. If you're extremely virtuous and you do something, you'll fall from grace and fall back to zero. So it's like that. The more good you are, the harder it is to get good. And vice versa.