With flawed characters, there’s much more to write about. A former writer on Seinfeld said recently that stories that focussed on Jerry were always the hardest to write because he had the fewest flaws. George and Kramer and Elaine had plenty of neuroses and quirks, so that allowed the writers plenty of material with which to play.
Remember the character arc?
Your character overcomes her/ his major neurosis by the end of the book. If your character starts out perfect, there's no change.