you know I think I could assist you with some sound effects, I am sound engineer, and I have some works that are ready to be sent, but from my prior attempts to invest into a project, I've had the members of the project claiming that I stole the sounds from various other places, considering this prior experience I am too reluctant to participate in any projects since then, overthewire participation sucks...
however, I do believe that if you want to create homeworld 2 in freespace, you might as well consider just copying the sound files from homeworld to this mod without modification