I have three more planned for the moment.
1. Adding nested comments
2. Activity Feed
3. ActionCable tie-ins
The activity feeds and ActionCable ones will probably come out in December.
If there is interest, I've been thinking about also doing an episode of taking a Bootstrap "Theme" and showing how to incorporate it within the application.
Yes, I plan on covering the refactoring soon. I wanted to get a bit more logic built in first. This upcoming episode, i'm doing something a little bit different. I go to meetups in my area and one thing that I've found is that people open have a fairly large disconnect from their production environment. So, I thought that a high level architectural overview could be beneficial to many.