Sorry to say, but the answer is absolutely useless!!
The whole Adobe Lightroom CC tools are looking nice but going in detail there are simple features missing preventing me to switch!
One missing feature (at least I haven't found it) is what texanjerry1 already asked: How can I start a slideshow over all Fotos with random sequence on Apple TV? I know, I need the app, but how to do? I guess it's not possible! Why not to implement such a trivial but helpful functionality!?
I use it e.g. while playing music on Apple TV. So I have to export all Fotos to JPG, import in Apple Fotos, there I can do. Not a really user friendly implementation...