High level of hardening in Lynis.

Hi everyone! I'm trying to raise the Hardening Index in Lynis to the maximum possible. But I want to do it in a way that keeps the system running smoothly.

I've reached a Hardening Index of 81, but I'm stuck there. I'm curious if anyone has managed to get it above 85. I'm really curious and would like to know if anyone has achieved this (while keeping the system fully functional and efficient)