As I wrote my answer to a Quora user who requested whether to use W3TC with Cloudflare I think the response there is clear enough. Start at the server. Start with NGINX. Buy hand crafted. I am the CTO at Wordsrack.com and work hard to deliver the best dedicated solutions to people who are serious about putting their best foot forward when it comes to IT Speed and Security services, high performance webservers and definitely everything WordPress.