I love the ability to quickly import papers with the PaperPile extension. What would make it even more awesome would be some way to tag/file the paper right upon import. Right now, I import and then open up PaperPile to file the paper, which adds a bit of effort.
That is a frequently requested feature and has an undisputed place on our roadmap. It’s not on the very top though so I can’t give an estimate though when it will become available.