Finally decided I'd lurked enough on this excellent thread that I had to post...
When I carry multiple lenses, I usually go for 18.5/2.8 (X70), 35/2, and a zoom (either 18-135 or the 50-230 for the built or natural environment, respectively).
My other prime is the Samyang 12/2, and 12/18ish/35 is pretty close to my ideal prime setup for city photography (though I might swap out one of the wides for the 16). For a more outdoorsy prime setup, I'd replace one of the two wides with a(n as yet nonexistent) tele, probably in the 200-300 range.
Had an X100T for a little while, but I much preferred the pictures I took with the 35. My glasses didn't get along that well with the X100's viewfinder either, so it moved in the world.
Adam D got a reaction from Patrick FR in Which 3 primes combo is your ideal setup?