Your question about alternative explanations for what causes historical change is a question of historiography, which can be roughly defined as the method or approach an historian takes to historical evidence. So, as you say, Marxist interpretations of history tend to emphasize economic and class struggle in its reading of historical evidence. Eric Hobsbawm's work and to a lesser extent EP Thompson's book The Making of the English Working Class are good examples of Marxist-leaning histories.

Two of the most notable historiographical approaches right now are social history, which emphasizes the study of social structures and history-as-a-process over individual actors, and cultural history, which (in my own interpretation as a historian of the book) seeks to understand cultural phenomena (like books!) in relation to politics, economics and other forces. In many ways these two modes of thinking about history stand in contrast to the "Great Man" theory of history, which was quite prominent in the 19th century. This approach can be summarized in a quote from one of its major proponents, Thomas Carlyle: "The history of the world is but the biography of great men". This is still often the way history is presented in popular culture. So, historical change can be seen to be caused by remarkable individuals (Great Man), social structures and ongoing processes and mass movements (social history), or by class struggle (Marxism). These are only a few different ways of approaching historical evidence, and it should be said that every historical period comes up with its own approaches. So no definitive answers about what causes historical change, but some useful ideas for thinking with!