To answer your points:
1) I understand not everyone will get how the registry fixes work, in the video I explained it slowly and clearly. I added the Leatrix link to the description a while ago.
2) After calling my ISP about the DNS the technical support said they prefer using Google Public DNS over their own too. Namebench reported a 187% increase for me.
3) The point about the third party tools I suggested is that they are 100% free and always will be. I would say that spending money on a registry cleaner would be a complete waste.
4) Square Enix did say that in dungeon/raids they will be reducing the 0.3 position checker. For me WTFast improved my latency from 480ms to 260ms, which is a game changer for me.
This video was simply my own experience of how to improve lag as well as make my internet browsing experience better and I was just sharing it in case it might be useful for others.