Richardb’s postulated workflow is similar to what I do. To import Fuji X-T5 RAF files and iPhone 17 Pro Raw (DNG) files into “Photos” would be a failed “IQ” test for me, since Photos won’t process Fuji Compressed Raw and in any case the file size (along with the iPhone DNG files) would bloat my iCloud storage, even after culling.
I store those original files in yearly folders. I use the Finder to batch rename the files “YYYY_MM_location_sequence). Nitro can do this too, (I like the underscore _ separator better than the hyphen -), but mainly, I also add Finder tags at the same time. I use Photo Supreme for folder asset management which will read Finder tags and automatically add identical Keywords (Graphic Converter can do this too, but it is an extra step with additional software). I then add those new photos to Nitro for editing (and additional keyboarding) and finally use the export direct to Photos using HEIC files. I would RATHER export using JpegXL (better compression and 16 bit color capable), but Nik hasn’t committed to add that option.
Once the exports are in Photos, I might use some of the 3rd party extensions (on1, Luminar Neo etc) to do final tweaks. The main thing is that the original (large) files are stored on local drives accessible to Nitro if re-edits are desired, and iCloud Photos manages the small processed photos and are globally accessible to my devices.