The problem with "Instant OFF GCD" abilities makes combat feel less rewarding.

[Malitias]

The stuff about UI is somewhere in the middle of this text:
http://www.secrets-eorzea.com/en/new...rets-of-eorzea
He says in the first 6 months he wants to have the game's UI improve based on feedback and then give players the tools to make their own add-ons.
If that is gonna happen, you can be sure someone is gonna do that sooner or later if SE doesn't do it.
I'll wait and see if they improve the UI to represent animation-locks. If they don't it wouldn't be a problem for me, but it seems there are quite some ppl having a huge problem with multi-tasking GCD and the animation of the character (pardon me if it sounds insulting or offensive. I do not mean to. Edit: Not anymore.).
So they should implement a cooldown timer for the animations. But, again, not change the mechanic, in my opinion.

Edit2: For targeting stuff etc. check the Dev-Tracker