I see that you buy many hostings, sometimes is not the hosting issue or performance.Litespeed webhosting is often expensive, example fastcomet monthly plans with Litespeed Server ist at $19,95 billing monthly.
Use a good webhosting then setup good theme and jetpack boost and use keycdn as cdn, with this your site will load fast in 1,5-2 seconds. Litespeed will not make that faster I never have seen full page loads faster than 1,5 seconds, maybe 1 second but that is very rare.
If you need Critical CSS/UCSS generation to remove unused CSS that is not free using LScache plugin. The plugin devs force you to use their service, Quic cloud, and charge a lot of money for it. Plus everytime you purge the cache the plugin generates all of the critical CSS again. So everytime you edit or publish a new post you wind up paying a bunch of money (depending on your purge settings).I have used both Nginx and LiteSpeed.
Don’t expect much difference but I prefer LiteSpeed because it provides it’s own Caching plugin ‘LiteSpeedCache’ which is free.
How's ur experience using Hestiacp? Kindly share..If you buy a shared hosting, choose Litespeed server
If you buy a VPS and setup your web server - Nginx is the best choice because it's free, reliable and a lot of free control panel there, ex: Hestiacp - which I am using.