So I’ve just now looked into bookwyrm despite knowing of it for a while. From what I can tell, it doesn’t federate with lemmy … please correct me if I’m wrong! And this seems to be largely because bookwyrm is largely user based, or at least that’s how mastodon sees it.
But it seems that lemmy and bookwyrm would actually be a good fit? Lemmy is communities with posts with comments. Bookwyrm seems to be books with reviews with comments. This feels like a one to one mapping could work well, no?
From what I gather, there are various bookwyrm instances with different focuses. So from lemmy you could search specifically to an instance for a book/community using key words, which would also work well. Then you could delve into the various reviews and comments etc.
More importantly, this would cross pollinate between the two platforms! And of course, any good review could be easily cross posted to any relevant community here, where all comments from here would also be federated with bookwyrm.
Some thoughts:
I find it works better for me to only follow bookwyrm accounts with my bookwyrm. I don't check it every day so it's easy to come back to record finishing a book and find my feed swamped by even a single user's microblogging activity. Book-related posts are just slower and fewer (at least amongst the other bookwyrmers I follow).
I follow my bookwyrm with my mastodon account so I can boost some reviews to mutuals with a shared niche interest. That works well enough. Aside from them being busy and not seeing my posts <lolshrug>
If I wanted to repost something on Lemmy (anyone interested in the original novels behind great operas? no? no? you philistines ;D ), I'd probably copy/paste what I wrote and link to the bookwyrm. Any discussion could happen on the Lemmy thread. If I wanted to save that discussion, I could add the link to my comments on the book.
That's somewhat more cumbersome than your suggestion but not much. My thought is that I'd rather have the bulk of a robust discussion on my microblogging or threadiverse account than my bookwrym because of that overwhelming my bookwyrm feed aspect. This would be especially true if my bookwyrm got spammed by a robust discussion by someone I follow about a book I haven't read. Easy to not read that thread on Lemmy.
As both platforms develop, it might be possible to create a good interface between them. I don't know enough to evaluate that. Just some thoughts from my experience using both mastodon and bookwyrm with each other.