There are countless plugins available for WordPress speed optimization and even a newbie can optimize the WP without plugins just going through some basic optimization tutorials. My question is very specifically about the WordPress speed optimizations plugins and the strategies that your tried so far and its results.

For me i tried like this:

Experiment A:
Litespeed Web server + SSD + RAID 10 + 1GBPS Port speed + MariaDB + APC +PHP 7.x + LS Cache + WP Optimize + Imagify + Cloudflare + Jetpack ( for image CDN ) + BJ Lazy Load + Custome tweaks in .htaccess and Php.ini

Experiment B:
Nginx PRO + SSD + RAID 10 + 1GBPS Port speed + Percona + WP Rocket + Redis + PHP 7.x + Mush It + Cloudflare DNS + Jetpack ( for image CDN ) + BJ + Custome tweaks in .htaccess and Php.ini

Experiment C:
Apache + SSD + RAID 10 + 1GBPS Port speed + MariaDB + APC + PHP 7.x + W3 Total Cache PRO + MaxCDN +Jetpack ( for image CDN ) + reSmush.it + WP Optimize + Custom tweaks in php.ini and .htaccess plus WP config.

I still don't remember the exact results from Gtmetrix and Google speed test, But the experiment A,B delivered the best and still we are using the same blend to our clients websites, Anyone tried this or any better suggestions?