I love the "New Posts" link above! It shows you all the new posts! Kind of like the "Today's Posts" under "Quick Links."
I also like the different ways to view a thread, the standard linear way is the easiest when the thread is simple but when there are multiple conversations going on in the thread the threaded or hybrid ways will be awesome. As long as people are actually hitting reply from the posts they're replying to.
Also "Multi-quote" is rather amazing. Especially considering the fact that you can quote from multiple forums!
I have not done the thread subscriptions or attachments yet. I should try those.
I don't think I'm hosting a 2016 collaborative playlist.