Very good subject cover and inside information.
The book covers current (2018) exam topic according to AWS exam blueprint, provides a few inside information on how AWS works, although not needed for exam, tests you at the end of each chapter and presents exercises so you can practice around. Having hands on in AWS is the most effective way of learning and fixing concepts for the exam and when working with it. Book guides you in most network technologies for exam and use cases, points to references for more detailed documentation when needed. However it does not provide step by step instructions, it's up to reader to find out more about it as it happens in real life, which I find good, as it e stimulates investigation.
One topic I missed is BGP entirely in details. Not that you need in all situations or even in the exam (as I haven't been tested yet) but I assumed some knowledge such as hierarchy of routing decision would be mentioned. This should be fine if it out of exam scope, and it does not harm going a step forward if you can reading more about it as well.