Add feature - double click on space between "sort by" bars expands the left bar
I believe PCManFM has this feature... not sure though :P... and can't check at the moment :D.
The screenshots below should explain it ;). The idea is that, when you double click on the space between two sort columns, the left column gets expanded, so that what might be the longest file name, file size, whatever, in the directory you're currently in, gets expanded, so that you can view the entire file/dircetory name ;).
I believe other columns don't have this discrepancy, (if you will :D), for example, the Date Modified column automatically expands to accommodate for the newly created date/time format, but not all of the columns behave the same (from what I've seen, correct me if I'm wrong).