Why do you discuss the question: "Bitcoin or Zcash?" I think the answer could be: Bitcoin and Zcash! Both of them can exist side by side. The use of Zcash´s anonymous transactions will increase and has become easier since the "Zcash wallet and full node for Windows" ( https://zcash4win.com/ ) was released. Zcash will be one of the most important coins in the next few years. Just like Bitcoin, Ethereum and Monero.