I find that, when writing bios, it’s really helpful to look at a list or a chart like the one above. Picking two or three traits from each chart and building a character based around them will give you a really interesting bio, because they will serve as a reminder that characters need depth and dimension.
Independent and clever.
Independent, clever, pretentious, and stubborn.
The first combination doesn’t come with any flaws, whereas the second will provide a more dynamic character.