As I understand it, after removing aka "customizing" at the bottom, "All Photos" has no structure at all for easy access to a certain date, so it does not suffice for large curated collections, particularly ones where location, month, day, and a sequence of intentionally related photos have been sorted. I read reviews and blocked the upgrade beyond 17.7.2. My many year set is a research collection as I am sure are others. Search by Day is a critical tool. Recent Day is not useful over time or necessary. Month and Day is not enough. So 18.1.1 Photos is not customizing.
Monuments. Archaeology sites with walls of varied heights (three stones make a wall), metal dig finds sorted by site and location and day (some jewelry, some not), frescoes sorted by city, church, chapel (Italy inserts names down to chapel automatically - is that removed?), sequences of photos from museums with the photo next to the image to retain the information, buildings with a photo of the floor plan and layers of excavated plans, etc.
Consider the citizen scientist. Rare bird report, Great White Shark report, cold stunned turtle, invasive species, report, etc. many of which are sent to the state or federal government. Some photos have legal implications where location, month, date are court references.
Small businesses have portfolios of work. Small towns have working committees whose photos support decisions with financial implications. It goes on.
I have in the past worked in and with photo archives and cannot tell you how important the location and day issue can be.
I just went to the formal Apple product response page with suggestion that I will pay extra for the original (now 17.7.2) version of Photos with Library, All Photos, Years, Months, Days Albums, search, and the sync button. Recently in Europe that sync button was key and still not enough as iCloud access was not 100% even after a successful sync.
Kills me as I had ordered new devices and was set to order more when 18.1.1 hit. Not so sure if I will keep them.
I hope these thoughts prompt others to provide more suggestions than "play with it a bit" with all due respect to Richard.