First of all, kudos, I’m a junkie for such optimizations myself. It’s a pleasure that your systems are optimized well, you sleep well and you’re proud :)

Two thoughts:

1) CloudFlare offers incredible service. What would need the team of netadmins/sysadmins can be handled via their UI easily. I use Argo in one project and yes, it is a very efficient tool. CloudFlare is becoming like AWS, knowing its tools is a skill. Maybe one day well see an official CloudFlare Solution Architect certification?.. :))

2) For such traffic heavy websites I don’t think there’s a better combination than Static Websites hosted over CDN, which is cached aggressively and for the dynamic part serverless as a backend. If you configure it properly (cache optimization, rate limiting to not get a huge paycheck if DDoSed, etc…) this setup is like set-up-and-forget-it, without the need to invest loads of resources into it.