The flexibility of tags makes sense, but this means that I then have to type in the same tag if I want to do multiple sparse collections of photos across folders. It's unintuitive compared to the picasa/iphoto workflow of dragging photos straight into an album.

Perhaps this could work if one could drag a group of photos to the sidebar containing the tag, but then that's bending the meaning of tagging.

Overall, I don't see why live photo gallery needs to break a workflow most folks are already familiar with (raw photos in folders/albums/tags). This organization is already used for flickr, picasa, iphoto (judging from screenshots), etc.