ist not the first request of this kind, but i still miss folders in the comp/timeline window for more comfort. it not always make sense to have something in a pre comp – especially when its animated – and to jump back and forth to adjust keyframes. it would be so great to have it all in one comp and just pack layers into folders and giving them a mask too. the set mask option does not compensate the miss of folders with masks – just think of a photoshop without folders for big composition jobs – unthinkable today : )
a big comp with many layers in after effects could be clear and structured with folder and a time saver.