Personally I prefer primes over zoom.
For wide angle landscape, the samyang 12mm, zeiss 12mm, fuji 14mm and fuji 16mm are all all excellent. The fuji 16mm was my favorite. I used the 12mm for ultrawide. Although The fuji 14mm is an impressive lens, I often found it too wide or too narrow, so I preferred the 12-16 combo.
Good luck with choosing your lens(es) and... Congratulations with your xpro
I'm not much of a "zoom person" but I agree with Luke, the 18-55 is pretty incredible and might be an excellent first choice for your new X-Pro1 which, by the way, is a pretty incredible camera too.
I'd also consider a fast prime when you can.
. . . David