Tbh, now that I had a good look at the forums, I don't think the idea was bad tbh. It was kinda cluttered, and I can see it's "somewhat" cleaner now.
The problem is subforums basically kill activity. There are only very few exceptions where a subforum actually performs really good, but if it's not visible, it will hurt activity.
Personally, I think the transition could have been done better by the staff. Atleast they could do is actually post a "Hey fam we changing the forum layout in a few days" or something like that, instead of bombing us with this big change in PC.
If it's okay, I'd like to suggest something.
I don't know if this is going to be in the UI Update, but I do like the horizontal forum placement going on in the generational forums, and I think that could be improved upon, maybe let it become tiles, like what is going on in the FF&W splash, where each forum has its own "icon", then the name at the bottom, and below it is the most recent post? For the parent forums, it could be placed above the tiles of the other forums, and take up a single row?
Honestly the only gripes with me about the transition is the lack of transparency between the staff and the members, most of the forums being granted subforum status, and Offtopic Forum in general.