The Art of War or War & Peace? Should your book be short and punchy or long and deep?

The reader can draw lessons on military strategy from War and Peace, but the reader cannot gain deep understanding of human experience from The Art of War.
For anyone who wants to write a book that conveys their knowledge, experience, philosophy, ideas, achievements in a way that will impact their readers’ lives, this is a choice you have to make.
Can I just skim the surface? Or is there more I want to express?