I use iCloud Photo Library which solves most of your problems except client side encryption - which I agree is a big negative in its corner.
It works very well if you're all in in the Apple ecosystem.
It works very well if you're all in in the Apple ecosystem.
But it really does Just Work. I’ve got basically every photo I’ve taken since ~2002 in a single archive, easily scrollable by date on any of my devices, searchable (on a map!). It works perfectly for me.
One day I hope Apple improves delta/library reconciliation, but for now, it's the best I've been able to find. It Just Works (for the most part).