Way more complex than Privateer ever was, way larger than any offline space sim, and simply cooler looking, X3 Reunion (which I have for Windows 32-bit) has come to OSX! Yes, that is a hell of a lot of great space sim/building/thinking/empire building for you!
It was available for OSX for a while, but as a Cider port - now the thing, native, comes in all its glory. hell ya!
X3 Reunion for OSX