My big curation-related grief has to do with YouTube playlists (the ones you can create with the +Save button on YouTube.) The list of playlists can't be sorted in alphabetical order by playlist name. It seems to be ordered either by playlist creation date and/or by when I last added a video to the list (with most recent playlists first.) I'd say the playlist feature is next to useless to me, except that I keep using it, ever so masochistically.

This is a recurring grief I have with Google products: poor UI and a seeming inability to receive and/or act upon feedback from power users.