It's very true that there is a lot of garbage to sift through. I would start by watching what I have not yet seen in any top 1,000 lists, such as....
http://www.theyshootpictures.com/gf1000.htm
or
https://www.amazon.com/1001-Movies-You-Must-Before/dp/1438050062/ref=sr_1_1
My favorite list book...
https://www.amazon.com/1001-Movies-You-Must-Before/dp/1438050062/ref=sr_1_1
Ideally succinct write-ups that explain why the movie is unique and important.