When it comes to strong, opinionated drawings, I know of no 20th century illustrator better than Robert Fawcett.
He did not simply record the world around him, he aggressively sought out nature's designs and amplified them with astonishing power and clarity. For example, this vigorous drawing...
...is just the seat of some old guy's pants in one of Fawcett's illustrations.
How many other artists could find such energy and beauty in such a banal subject? Next, look at the designs Fawcett finds in the folds of Sherlock Holmes' cape...
...or in the anatomy of a hand. Now that's what I call drawing!
More bold designs in the pants legs and clothing of this couple stranded in the desert:
Even the most delicate lines reflected Fawcett's distinctive personality. Note the hair of this lovely young lady from a P.G. Wodehouse story.
Some very astute observers of illustration art, such as Mike Vosburg and Leif Peng, recently paid fresh attention to Fawcett's work on their web sites. He has been gone for 40 years, but Fawcett's art always rewards attention.