I will start off with the positive – I very much like the “Photos” app on the iPhone and also on the Mac. I have been using it as my primary tool to manage my 200K+ images. It took me a while to realize that not all my updates and changes are actually pushed and sync’d all the way immediately.
For example, when I add a new pix to my album, that actually does seem to get propagated all the thru almost immediately. Even some of the metadata, i.e., Geo Location, Key words etc are also saved and pushed almost immediately. Where this does not seem to happen is in the case of defining / identifying a face.