So many great suggestions in the linked thread, I went through it liberally clicking the but it would be great to be able to “Like” at the thread level. Then having some sort of way to sort or search by most-liked threads. This would help forum readers find the most helpful threads quickly.
This is a little different than just looking at the total number of “Liked” posts in a thread, because some threads are very long and have circular discussions, and may have a lot of posts that get a lot of “Likes,” but the thread isn’t particularly helpful overall.
Maybe it could also be possible to “Dislike” a thread. That would be sort of nasty and personal at the post level, but potentially helpful at the thread level. It seems like there may always be a lot of “I’m Mad!” threads, and some people will like them and some will dislike them. Allowing both Likes and Dislikes of a thread would help keep that in balance, so the “I’m Mad!” threads won’t inevitably rise to be most-liked.
It’s not quite the same, but I think it meets some of your needs - “star it”. Between the Soylent logo in the upper left and the thread title, there is a grey star - click the star and it changes to a red star.