Some more minor progress.
First thing I did was revisit the timing, the whole sequence didn't feel right to me after looking again last night and I realized my sim's frame rate and what I had in engine didn't match... duh.... so I've fixed that up. I do now feel that the splatter doesn't fall quite fast enough (looks a bit floaty) but the whole sequence feels better to me.
Manipulated materials a bit, and added an animated pass of high-frequency liquid noise detail. It is a bit hard to see, but during the explosion I blend in a top down projection of water-like ripples that scale up from the point of impact to a halt as the liquid settles. Then I blend them back in and scale them inwards during the initial suction moment.
Also I have started making the first set of 'magic-like' effects, to add some intention and direction to the entire effects. Early days still in that regards, but now I have a fancy automatic ribbon spline blueprint maker that I can use to ensure I get high quality curves.
I definitely wasted a bit of time trying to go down the particle ribbon route. I first got them working with sequencer scrubbing, and then set up a good deal of animation with them that I was theoretically happy with, but ultimately had to scrap the Cascade ribbons because the speed at which I wanted them to animate meant I couldn't get nice smooth curves without more tech investment.
Anyway, I'm happy with what I did manage to get done, though I think I'll have to revisit the textures and look of my magic bits.