I will make it if you're willing to pay, not sure what do you mean by reaction matrix because particles are dont have colliders and are simply points in the simulation, currently particle size is for visual purpuses only I could use that for colliders but just asking for clarity.
It might take some time as I am currently focusing on project for #SoME3 making a video about 4D rotations, that will take me around 2 more weeks to make. I'll need around a month to do it.
I could send you the results as videos of the features, then you pay and I'll make it public if that's fine.