Ok, nice to see all those comments... it seems the 27mm is going to win this "battle" for street photography!
GordonRussell, I was thinking about a street setup very similar to your first one, but with X-T1 instead of X-E2 for better control, grip and EVF.
The 55-200mm and the 18-135mm would be eventually in the future to complement or replace the 18-55mm, which actually turns out to be a really amazing lens, I keep reading wonderful reviews about it.