I’ve been tinkering on something adjacent, to replace my Instagram usage rather than Photos.app. I was thinking of a sort of “album as a blog post” concept using Ghost, which could be a single image per entry, or a series of images with optional prose interspersed. The idea is to take an album and auto-generate a blog entry with inline photos that can be edited in Ghost. It can also pull out photo metadata and create a map, etc.
Unfortunately Ghost isn’t as modular as I hoped so it is involving lots of edits to the source, and automatically extracting album metadata from Photos.app has also turned out to be difficult.