Spotted extensions capabilities for Photos as “one of the many new features” listed on the summary keynote slide at the end of the OS X 10.11 presentation. A glimmer of hope for Photos!
Are you using the new Lightroom; the version that's the same (mostly) on desktop and mobile? Then you may have noticed that a few features are NOT actually on both platforms. The ones that get me the most are Copy Photos (ie duplicate photos) and Batch Paste. I've found a way around it… in a round about sort of way. Check it out!