If you type 'os' in ranger, you can sort files in ranger by size. I'm wondering if it would be possible to make it "recursive"/"cumulative" in how it interprets file sizes, similar to how the "du" tool works, ordered by how much total space would be freed up by deleting each file/dir. I realize there would be some performance cost in recursively analyzing big directories, so maybe that's too complicated to implement or out of ranger's scope...