Though it seems like it's more suited to fully text based scripts. The format I was messing with was full of markers to e.g. change the facial expression of the speaker's portrait, play sound effects, etc. (mid dialogue!)
Makes me think about how script/dialogues are written and formatted internally in other mediums. Umamusume in particular stands out in my mind; it has a lot of movement and actions as the dialogue lines are spoken. Sounds silly but they really do make it feel more dynamic and alive.