"Small is Beautiful" is sort of a difficult read. I picked up a copy of "Small Is Beautiful in the 21st Century: The legacy of E.F. Schumacher" by his daughter Diana Schumacher. It hits all the main points while being a little better organized.
I went a little nuts with modern anthropology and absolutely adore Giddens. He was actually the person I was visiting in London when I bumped into Graber. "The Consequences of Modernity" is a bit dense and filled with jargon, but I love it.
There was another post I commented on and mentioned "Everything Was Forever Until It Was No More," and while it's not a general-purpose discussion of how we model social systems, it is a great read. It's where the word "HyperNormalization" comes from and tells the story of the last generation of soviet citizens who noticed things weren't working too well, but grew up in a world where there were no alternatives to state bureaucracy and politics.
I also read a fair amount about pedagogy since I'm interested in structured systems of developing denotational systems for modeling human knowledge with the objective of communicating said knowledge. I love Sylvia Ashton-Warner. She wrote an autobiography called "Teacher" that's worth a read. I hung out with Seymour Papert and Cindi Solomon when I was a kid, so I have to mention Mindstorms. And Freire's "Pedagogy of the Oppressed" has some interesting bits if you can handle the 70s communista jargon. It's not full-on marxist, but if you're sensitive to such things, it can be distracting. But... what they all have in common is a framework for how to communicate (potentially) complex models and knowledge maps.
Read everything you can find by Jung, McLuhan and Claude Levi-Strauss.
"Eros and Magic in the Reniassance" by Ioan Cuilianu. Then read it again because it's hard to figure out what you just read when you only read it once.
For fun I've read some of the articles and books by Rory Sutherland.