I consider this a critical feature for the most critical activity that you need to acomplish while you create a community: GROWTH.
A community it is not stackoverflow, where, I guess, most traffic cames from search engines.
So, that's why I think some features working there, not necessary are good here. And viceversa.
If you want to create good conversations (which is one of the missions of Discourse) you need to build a context where community happens and grows. To startup a community, you need to use a lot of different techniques. One of the most famouse technique is "fake it until you make it" from Reddit guys.
I know, it does not seems the ultimate tool to growth a site, but it works. You need some way to give signal to newmembers about this new space, and the most important signal is that it is growing. Also signals about how many people used your site today, yesterday, now, etc, are very important features, they help a lot. Discourse has sources and interesting data to build something interesting with this.
There is a lot of evidence that in Youtube, people tend to see and share videos that has already seen by millions. In facts, people judge a video using the number of views of the videos. (Ref: [Building Successfull Online Communities])
Robert Cialdini's entire book about Persuasion.
Building Successfull Online Communities: An empiric study by MIT Press
In short, would be great if there is a way to see how many people is on a site, on a topic, who they are, etc. Like the "old" forums.