Firstly, official support for voice-over communication like Teamspeak SE mentioned a long time ago that it would not possible due to the fact that it would unfairly impact on PS3 and PS4 players (who would not have access to it - the voice-over function for PS3/4 is controlled by Sony not SE and thus would have to be separate from PC players - completing destroying the whole point of having console players and PC players together on the same servers). So sadly this will not be possible.

Individual Limit Breaks have been often requested, but other than the level 4 Limit Break being redesigned to be determined by the Job of the person who executes it instead of simply by role, sadly I think will be the closest you will get an individual Limit Break I'm sorry to say.

Finally I remember Yoshi did say a while ago that a FFXV tie-in event is coming, and hence a FFVII Remake event is also possible... but it would probably involve a FATE battle as usual (because they're much simpler and faster to implement than having to code in a full trial battle like an optional boss). Either way, I'm certain SE will do something to tie-in with the FFVII Remake when the time comes.