I still have to read Broken Money, I'm waiting for an audiobook version to be available on Audible in my region since that's my jam, but yeah, I've heard great things about it, and now that you say that it closer to Layered Money than I might give it a read on paper instead of waiting for the audiobook to be available.
I recommend Alvaro's book for 2 reason's:
  1. He does a great job at explaining not only how Bitcoin works but why it's important, his book is a great introduction not just to the inner workings but at the philosophy behind it.
  2. I know the guy, he's chill about all of it and very level headed, maybe one of the people who I know knows the most about Bitcoin without being a deranged fan, he's a great person.
This is the first time I hear about Digital Cash, I might give it a read, but at this point I don't think it would give me any new information I don't already know heh heh.