You should definitely quit your job. You’re using your job as an excuse not to do what you are really meant to. Obviously, who you are and what you do are solidly connected in your mind. Chances are your very spirit is entrepreneurial, or you have a deep-seated disrespect for all authority, or you have to do something that is eating at you for your neglect it. Quit already. Go, start your own company, write the novel, paint the picture. People like you, at your stage of life really shouldn’t be working for anyone else.