Do you want Photos to show its library selection dialog when it opens? Here’s one solution without the Option key.
There are problems with backups of Photos Libraries and evicted items in iCloud Drive. Here are full details.
Running High Sierra? Do you keep your Photos Library on an external drive? Do you realise that backing it up using Time Machine is likely to be a waste of time?
In 10 or 20 years time, where will today’s photos and videos be? In an archive? Have you started one yet?
Never underestimate the time and effort involved to enter data for old photos when you scan them in.
How is it best to move my iPhoto/Photos and iTunes libraries onto a networked disk?
What is the best way to copy images from Photos? Its library looks a real mess.