Hmm, that's an interesting read. In the alignment chart I linked, Mycroft is the true neutral and Molly is lawful good. But generally speaking, I think I can see Molly as close to neutral, rather than lawful. She does bend the rules for Sherlock and in general (office romance, all that). But I tend to think that she's good rather than neutral or evil.

Amoral characters are generally true neutral though I'm not quite positive that all true neutral characters are amoral; I feel like there may be corner cases out there that I'm not contemplating. And while I'm rather fine with the idea of Mycroft being amoral/true neutral, I'm less convinced of Molly...simply because I think she, like Sherlock, is on the side of the angels.