This is NOT yet-another book about cryptocurrency. The book is about how Russia and China are likely to use digital currency technology (which was invented by the crypocurrency crowd) to create a new global-scale digital currency system designed to steal the title of global reserve currency away from the U.S. Dollar, which has held that title since the end of WWII.
The rationale for "Beyond Blockchain" is that right now the world is all in a frenzy over blockchain, the distributed database that makes the Bitcoin cryptocurrency possible. The point is, this is NOT yet-another book about Blockchain. Rather, it's about what the future of digital currency will look like AFTER blockchain is forgotten. Hence the title Beyond Blockchain. So think about how to graphically express the concept of what comes next after blockchain. But frankly the Beyond Blockchain part isn't the most important part of the title. It was chosen because Blockchain is such a hot SEO buzzword. The subtitle "The Death of the Dollar and the Rise of DIgital Currency" is what the book is really about. That should be the more prominent component of the title visually
The book is about how Russia and China will use digital currency technology to try to dethrone King Dollar, hence the subtitle/tagline "The Death of the Dollar and the Rise of Digital Currency".
The basic premise of the book is Russia and China are probably already hard at work to use the technology invented by the Bitcoin guys in order to try to take the title of reserve currency away from the Dollar.
Please think about how to use graphic elements to depict Russia and China attacking the US Dollar, using digital currency technology as their weapon of choice. Note - they're not attacking the United States as in the country - they are attacking the DOLLAR as the center of the global financial system. They hope to use digital currency to create something better so that the rest of the world can be convinced to ditch the dollar.
Just to be clear, the book IS very much about digital currency technology, so graphic elements depicting digtal money are a good idea. But it's NOT about the existing cryptocurrencies such as Bitcoin, so something like the Bitcoin logo or any of the other cryptocurrency logos doesn't fit.
The premise of the book is that the U.S. Dollar WILL eventually be replaced as the world's reserve currency by a digital currency. The question is whether the U.S. does this or if Russia/China beats them to it. In the book I describe a "coming space race" where U.S. is pitted against China/Russia to see who is first to replace conventional money with digital money. If you can figure out how to express these concepts graphically, you're on the right track!