Understanding Photos Memories & iCloud

Hi,

I have some questions concerning the Apple Photos App. I hope you can help me as I didnt find the answer online yet. I have imported about 10.000 photos into the app - my iPhone / iPad has synced about 2000 fotos yet.

1) While my iPhone already shows several memories (after 5 days of using), I get only 2 memories on my mac. Also on the phone, when opening one memory, it suggests other similar memories. I don't see anything like this on my mac? Any idea about that?

2) Inside a memory, you see the summary of the "best" photos. Even if this works quite good, its far from perfect. Therefor I would like to select the pictures, which should appear in the summary. I did not find that feature anywhere?

3) Faces. It seems that Photos skips a lot of pictures with people in it, whithout recognizing any face? Anyone the same problem?

4) I am using the iCloud library, which will have about 110 GB if uploaded. Do you know, if the Mac library is syncing both ways, while uploading? Or does it sync the download, if the upload is stopped? The reason for this question is, that Photos on Sierra does not get the latest photos from my iPhone - i am wondering if the upload process is the reason for that?

thanks for responding

best regards