I'm the lead author of this textbook/lecture series. It's been a couple of years, and we've been thinking about an update. Let me know what topics you'd most like to see. Note that our goal is not to much to teach the details of specific cryptocurrencies as the concepts underlying them. For example, covering Byzantine Fault Tolerance and its application to blockchain protocols is high on my list.
Could you cover the topic of SegWit? Since Bitcoin core has adopted that as their first scaling code change post 1MB blocks, I think it would be helpful to understand what's going on with that.