

What is NOT important, and a waste of time, money, and energy; is when you worry about unimportant, nit-picking details in the design. No body is going to care if Homer Simpson has 2 hairs on his head or 3 or 4. No one is going to stop watching Family Guy if Meg Griffin was designed with square glasses instead of round glasses. No one is going think South Park is any less funny if Cartman's double chin line was removed.
Not to say all shows can get away with bad designs. But you need to know what is important in each specific show you work on.