biochroma sounds plausible, but the rest don't. In fact, the duralumin soothing you just describes sounds like the exact opposite of what should be shown.

The biggest problem is that your depiction places more emphasis on the fact that vin is burning duralumin, instead of on the fact that venture just got a taste of what it feels like to be dead. A glowing flame suddenly going supernova sounds like the exact opposite of what I imagine a duralumin soothing would feel like, and investing all of this screen space (literally half of the screen, gracelessly split down the middle to show this fireball) takes away from the real reason this scene was awesome.

Soothing is not a combat ability. Literally nobody else in the book has even considered its potential to actually harm somebody, and its grouped as a category of allomancy that relies so heavily on sublety that it's considered a useless power if someone is even aware you are trying to use it. Vin uses this power to crush venture's mind, and he's left with borderline PTSD for the rest of the entire book just thinking back to that moment. This is what was important about the scene, not that vin burned duralumin so strafe got pale and fell down.

And parshendi rhythms would flat out not work the way they are described in the book, no matter how you try to score them. You could easily have a character talk in time to a beat. You could easily have two characters talking in time to different beats. But what's the significance of that? How do you go from "these two characters are talking in monotone to two different beats" to understanding that one of them can now attune the rhythm of wrath and the person they are speaking to has never heard it before.

tl;dr - What you've proposed is exactly the kind of thing I fear happening, because it would ruin the actual impact of these scenes. Your problem isn't portraying that something is happening, but why that thing is significant -- vin burning duralumin isn't important, the lasting emotional damage on venture is. It can be done, but you have to have an understanding of how to tell the story using a visual medium.