Pompino is SS only. Kaffenback or Uncle John may be better.
Cotic didn’t get a brill review from raod.cc, and the weight bothers me slightly. It’s also 135mm spaced at the rear, so you’ll need to have specific wheels built.
Also have a think about Surly.
I love the look of the All City Nature Boy: http://allcitycycles.com/bikes/nature_boy
Discs have only just been permitted for cross racing by the UCI, so expect a bit of time for the technology to trickle into the more mainstream cross brands. Once some decent lightweight STI compatible discs become available, I think there will be more avialbility.
I’ve just built a SS cross bike from my old road fixed, and it’s good fun. However, next year I’ll build something light for racing (maybe a Milnes or decent Kinesis).