Would be nice to package sox as a VST plugin.
This would enable users of VST plugin container programs (like Cubase, etc.) to use sox as it does other VST standard audio plugins.
Could start out with a simple command-line-ish interface. Maybe a new VST -t type for sox that allows streaming with VST plugin via pipe to sox stdin and/or stdout.
prof-spock has done this at https://github.com/prof-spock/SoX-Plugins