I've not found a good alternative and I'm curious to see what is suggested.
What I'm doing for now:
- backing up all my photos in original quality to my NAS
- backing up all my photos in space saver quality to Google photos
You can store quite a lot with the free 15GB. And if you need more, create a new account for your wife, add it as a partner and all photos will show up as if they were on the same account.
I don't know how many wives Google allows, I've only tried one so far. But if they allow polygamy, you can get a new wife whenever you run out of storage.
TL;DR tell your wife the only way to return to Google photos is for you to get more wives.
AFAIK, Anonymous means that it contains no PII.
You can personalize content without sharing PII.
E.g. via preferences or settings.