Spiritualist and xenophobe.
Xenophobe isn't strictly how I play all the time, I'm usually diplomatic, but I like having the option open to use livestock and I NEED xenophobe to do that.
Spiritualist unlocks a lot of features I enjoy using, as well as priests when I often focus unity. Plus it's good synergy with biological and psionic ascension, my two favorites. Machine Age will probably make me like synthetics as much as those two, but it will also make spiritualist machines possible so I don't think it'll change my ethic preference.
The exception is I enjoy materialist with Byzantine Bureaucracy, although that's mostly because Relentless Industrialists is locked to materialist. I still don't build robots.