At the original FFXIV launch there was a system called path companion.
http://ffxiv.gamerescape.com/wiki/Path_Companion
It was cool because they came with some story and were supposed to be able to battle alongside you in the field. I feel this would make me feel a closer bond with my companions and character npcs in the universe, besides just main story quest.It would make XIV feel more in line with a traditional Final Fantasy game as well. I really want to see this happen..
I would like to see them brought back in conjunction with a trust like system.
http://ffxiclopedia.wikia.com/wiki/Category:Trust
Perhaps even throw in a conversation system to learn more about them and gain trust.
https://www.youtube.com/watch?v=XlCeHL9gAS0
Please leave any feedback or suggestions!