I think lemongrove has a point. It would be useful if there was a facility to refer readers to a previous post in the same thread rather than quote from it. Quotes can sometimes lose context. Perhaps it would be possible to select a previous post and include a bookmark of some kind in your own post so other readers can click the link and refer to the post in question, then return to whatever they were reading/writing. This is technically quite difficult and a bit of a challenge. I sometimes refer to the time and date of a post for clarity but it's a faff for both the reader and writer of a post.
As to having a ‘like’ button, I dislike the idea that some GNs might feel socially excluded because they didn't get enough ‘likes’ and needed to appease their GN ‘friends’! (I include myself in this group, I was always last to be picked at school!)