I'm currently inspired by Robert Fawcett and his insistence on trying to capture observed detail as opposed to formula.
In his book, On The Art of Drawing, he suggests an artist is better off drawing the model inside the environment rather than just the model because the skills used to draw a model are no different than the skills used to draw an environment.
And ignoring one for the other results in neglecting one's ability to correctly observe how line and tone interact as well as one's ability to design and compose pictures.
A previous (and awesome) teacher said the same thing to me.
I've got a long way to go.