If you are worried that China may own one of the root certs in your browser, remove the certs you don't trust. Hell, remove all the certs. Every mainstream browser allows you to do that. In most of them, you can even set up permanent exceptions for Amazon.com after you strip your certs out.
Meanwhile, HTTPS/TLS has over a decade of the most intensive study anywhere on the planet, and your favorite half-assed ad-hoc bespoke random "crypto-cat" scheme... does not.