Came across a new site for readers that is basically a lot like GR and LibraryThing. It's new, so I've found it slow to use at times (not enough servers?) and a lot of features are still being added. A lot of books don't have book covers showing yet.
I don't know who owns or operates Leafmarks, but it appears to be privately owned, quite possibly one of about two that aren't Amazon owned?
Here's a link:
https://www.leafmarks.com/
I imported my books from GR using their export to cvs and it worked perfectly. I'm not sure I need another site, but it doesn't have ads (yet?) and it seems well-organized.