The single biggest issue holding back FFXIV needs to be specifically addressed.

[Rohab]

I have to agree with what ReapKarmah said in the YouTube video;

"You did a marvelous job at proving this issue is real. Thank you! Seriously though, I understand MMOs have lag...but really? This is unacceptable!
Square Enix, to them I have one thing to say: Stop focusing on new content and optimize what content we already have!"

Mainly the last part. Optimizing what we already have instead of implementing new additions to the game, such as materia, chocobos etc. I think all this will add further problems.
I'm all for new content, but with the game the way it is, all efforts should be focused on fixing the 'frustrating' aspects of this MMO.

I have read most pages in this thread, and the replies from the Dev. I understand they are working on fixing these problems. Still, they need to be addressed promptly.

Just my thoughts though.