OK! I personally find the narrative text quite elaborate for a first pass, I spend a lot of time polishing my text but it’s quite not as much “novelized” (I’m also not a native speaker and don’t read a lot of novels in English, so I just write in simple English; and my narration phases are told as if the character was speaking casually).
Indeed, I don’t have an easy solution for the sprite changing and the narration box reappearing. In other games I’ve played using NVL mode, either there were no particular sprites shown (sound novel) or the sprites were shown on the side (Magical Revolt: Mimiko’s choice).