Something I just recently found out that I wish I had known all along, while holding a trigger pressing the opposite shoulder button will target mobs and only mobs. I use xbox controller but for example on ps3 while holding R2 you can press L1 to target the nearest enemy and continue pressing it to cycle through the other enemies near you. Or hold L2 and press R1 to target. Works perfect for fates since it ignores other players and their pets, chocobos, minions, and anything else.