Thanks for the answer Keith and the confirmation on my suspicions. I really love the xt1 and xt10 actually, quite frankly, they are much the same, but it seems I need the 14mm. I have at present the 18, 35/2, 18-55 and the 55-200/3,5-4,8.
You probably need something wider than 18mm (at least if you are into landscapes, among other things), but you do have several choices:
XF14
XF16
XF10-24
Zeiss 12
and a whole bunch of manual focus alternatives (native and adapted)
The Fuji 16/1.4 is the best wide angle optically for Fuji. In fact, it puts a lot of pricier 24mm FOV glass to shame from Nikon, Canon & Zeiss in my opinion. And it is sharp and contrasty right out of the gate @ f/1.4. It is an amazing piece of optical engineering. And of course it is weather sealed.
The 14mm is not too far behind the 16, and the 10-24 is very good for a zoom, but is a touch behind the primes at the wide end and a bit more dodgy at the long end (20-24mm).
The Zeiss 12 is nice and wide but it is not well corrected optically for distortion and the edges suffer once extensive software correction is applied.
I have the 16 on order (arriving this week from B&H) because I'm a lens junkie, a wide angle junkie and a sucker for fast, wide lenses. I will likely carry the 16 when I plan on doing interiors in low light, want the close up, wide open look or want to minimize perspective distortion for architecture. I suspect the 14 will still be my go to wide angle for landscapes though unless the 16 blows me away image quality wise. I was going to get the 10-24, but just couldn't see giving up on the stellar 14, 16 and 23 primes - 3 of Fuji's strongest lenses.
There's no wrong choice, really. I don't have the 16 in my hands yet, but if I could only have one, it would still likely be the 14 because I like the focal length so much.