What is the IMPORTANT difference between Beethoven and his predecessors Haydn and Mozart?

Beethoven used more dynamic contrast and angst (for lack of a better word) in his music. Before, with Haydn and Mozart, the music was very linear-- beautiful and emotional, yes, but more based on melody than anything else. Beethoven was the first to really use contrast in tone and dynamics *and* innovative rhythms to create interest in his music.