I feel like the explosions were pretty good about halfway through, but that they took a major turn south when you started applying light to them. They became incredible hard shapes that don't make much sense I feel.
Dust is not a very hard material even when it's quite thick, and it tends to be extremely matte (because it lacks a surface), see if you can't get them to stack so that there's basically 2 zone (smoke in light on top, smoke below that's shadowed) with very rare instances of lighter or darker where it's particularly sculptural.