I kinda like the way cohost deals with comments.
There is the more "casual" comment under, but if you want to add something else in a reshare, then that itself gets its own comments bit. Adding media, adding info or more links.
It really does feel like a mix between tumblr and twitter, and much clearer and easier to follow than tumblr had. Then again, I never did learn how to handle tumblr. Hm.