Was trying that with an experimental story, with seven major characters. Gave nudges to the characters to help them contrast in their virtues, their flaws, their interests. . . .
One has decided not to be the angry soul. Especially since another character has decided to make her bad temper known, so orchestrating means moving them farther apart. And excludes a few other faults that pop to mind, such as sloth, which other characters have.
And if I just let the tale give me one, he may not get one -- muses are unreliable -- and if he does, he may be too similar to another character. They need to be foils to each other, and means of instruction.
Variations on a flaw, perhaps. Though even though the other character is peppery, with a quick but not long lasting temper, I don't think he's going to be bitter and hold long grudges.