Be able to flag papers you want to read more carefully at a later moment
Add a new category under My Library similar to Favorites but named Flagged for papers that are extra interesting but don't qualify to be favorites. This can be useful as a "temporary favorites" catalog for instance if there are some papers you need to read more carefully later on or if you want to keep them highlighted while writing a certain paper or preparing a talk etc.
Bw Bw commented
I second the idea of having multiple flag/star colors. Or even have the background of the flagged paper be a different color (as opposed to the typical alternating white and blue, like OSX finder does). It would be nice to also sort by the flag color. That would help when adding a paper and its supporting information along with it. Have one tagged 'red' and the other 'green' and being able to simply differentiate between the two and sort by one or another.
Stephen Prunier commented
I would love to have a feature like this. I always star all of the papers I'm using for writing my current paper, but there are others within a folder that I may like but are not relevant for that particular paper. It would be great to have more than one way to mark papers. One simple way i would see to do this would be have more than 1 color of star that way I can keep all the papers i like as a gold star, but maybe i'm working on a paper that needs just the green stars this time around.
Shawn Perdue commented
I always use the "star" feature for this.
Bala Kailasam commented
It would be great if we can set a reminder to read or send a reminder link to an app like Omnifocus. What about enabling IFTTT, so that when a new file is added there is a mail that is sent as a reminder.
Joe Sapp commented
you can make this pretty easily yourself with a tag or a folder. Folder seems closer to what you want so just click "Create Folder..." under "My Library" on the left, name the folder 'temporary favorites' or 'flagged' or whatever else you'd want, then just drag any qualifying files there. pretty easy.