Re: portraits and street
I picked up the Fuji because I wanted to do street photography without carrying around a backpack full of lenses. My other cameras are a Sony A7r2 and a Nikon D810, so I'm used to having the extra pixels and processing latitude of a full frame. With the fuji, there is a little less exposure latitude and ability to crop. The Fuji kit is lighter, stealthier, and the handling is better--MUCH better than the Sony--so you get shots you wouldn't otherwise get. But the point is, you really want stellar optics to make the most of the smaller sensor. The 50-140 is a beast of a lens, so keep that in mind. Do you really want to lug around that big of a lens for your small / light mirrorless?
The 35mm f/2 is sharp and fast--great for street--and doesn't block the OVF. Haven't tried the f/1.4. For street, you often find yourself in low light levels, so f/2.8 is often not fast enough!
The 56mm (85mm equivalent, let's not forget) is even sharper and faster, and should be fine for portraits.
This site has bench tests on pretty much all of the Fuji lenses: http://www.lenstip.com/index.html?producent=66&obiektyw=1224&typ=0&moc=0&sort=
The blur chart of the 90mm is amazing: http://www.imaging-resource.com/lenses/fujinon/xf-90mm-f2-r-lm-wr/review/
Here is my site with street photos, all these were taken with the 35mm f2: http://www.ericyphotography.com/#!street/f0gtw
p.s. gordonrussel76: I like your street shots with the 90! I'll have to give that one a try. '-)