Hey this was also the first fluid sim paper I ever implemented! I haven't done any grid-based simulations (except maybe the classic "Real-Time Fluid Dynamics for Games" by Jos Stam), but I've been able to greatly improve compressibility by using "Position-Based Fluids" by Miles Macklin. Someday I'll dive into WebGPU and post a JS version on HN...

Short clip of my implementation here: https://imgur.com/a/2IARiBq

I like the different fluids in your sim though, I may try that myself.