If I had a vote, it would be for keeping the forum mostly as is. It is functional. It is easy to use. It is fast. It runs nim code.
It does not support nested threads. Neither do many other popular forums, and in my opinion it results in much more focused discussions, especially in smaller communities like Nim currently is (and no, this is not an impediment to growth at this point) It is a fine example for a web+db application written in Nim, for anyone who wants to study such a thing. Also, like HN, it is my impression that the lack of notification contributes to a lively focused discussion.