I strongly agree with you that zero knowledge protocol is a way of proving one party to another party that one party have secret but party would not this close that secret upon everyone as well as if I talk about first party then it would be prover and second party would be verifier.

ZK-STARKs and ZK-SNARK both are terms which are similar in some aspects but most of the time these terms are different as you have also illustrated many of the differences between both of them as well as you have also explain some of the important privacy mechanism that are used by Steem blockchain.

I wish good luck and success to you in your entry but want to see some more depth in some of questions next time.