You wanna say something during a battle? just stop for a few seconds, no1 will kill you for that...
Or talk to the mic.

As has been said multiple times before, nobody is buying the "communication" bullcrap in this day and age. Other MMO's are fine, XIV should be fine as well. People aren't going to accept less involving gameplay to be able to chat in this 3D MSN because they don't accept it in any other MMO either.