Your artwork is built upon your drawing. Now with this said, I do understand that many accomplished artists paint without a detailed drawing and come up with an accomplished painting. However, I am sure that they had some training previous to this step in their career. Without an understanding of perspective, composition, different applied lines, light effects, negative shapes and more, your work will most likely stay at the same level.
I can't tell you how many art show jurors have said that the weakness in a painting can often be the inaccuracies of the initial drawing. I even had a very well accomplished artist admit that they missed the "Best of Show" Award by having an inaccurate perspective area in her painting (This told to her from the show juror). This was for a realism show.
If you have a well thought out drawing which is technically accurate, you are more likely to have a better, more pleasing outcome.
|Before Drawing-Adult (above)|
After Drawing-Same Adult (below)
|Before Drawing-age 8 (above)|
After Drawing- age 8 same child(below)