While cutscenes are nice for discussions & events happening, the new Talking Heads effect added for Legion can be great for one-off lines, hearing passing discussion, and overall displaying story content without stopping the player in his tracks (and with better visibility than the Display Text effect).
It would be nice to add an effect to use a Talking Head, selecting the model shown, name, and text to display (In a manner similar to quick cutscenes, maybe).

Postpone this after 8.0. Talking head (and other alert type frames) placement is being tweaked on BfA.