I think it's a pretty good list, but a lot of it is comprised by well known movies that will always appear on a list that wants to be representative. What I mean is that there are many obvious choices, and a lot of quality cinema. Experimental films and more "commercial" films are sorely missing. Too bad I've only seen one third of the list. But "significant" is a difficult term to pin down. Significant for what? The influence on World Cinema, the influence on German films, box-office success, etc.