This guy disabled C-states. I don't know if that's a good idea. Doing so may break sleep/wake.
Also, he has AVX offset at 2. I haven't tested recently, but the last time I did test AVX offset with macOS, it just keeps your overclock at the AVX offset speed 100% of the time. That means if, for example, you have your multiplier set at 51 for 5.1GHz and AVX offset set to 2 like this guy has in the video, your CPU will only ever get to 4.9GHz in macOS and never go beyond that.
Lastly, you can probably lower the VCCIO and System Agent voltages a bit. Most preset XMP profiles overshoot on these quite a bit. Lowering these two can potentially extend the life of your IMC and/or RAM.