Thank you for the examples, LotusJeff and Canapin.
I notice in the category approach that people don’t always come up with a gripping topic title – but it looks like even the “Hello”, “Hi”, and “New Member” posts do get some attention.
– Thanks for this input. I guess seeing the same “Introduce Yourself” topic reappearing over and over might not be especially compelling.
The other thing I notice is that these forums center on a shared interest/hobby involving common stages, and that invites encouragement and advice. I’m realizing that doesn’t really map to my Q&A forum, and introductions miiiight not end up adding much value in our context… 
I can see how they’d be great for a forum about sharing ongoing personal experiences, though.
I appreciate all the comments!