Carruth is way more interesting than Malick.
Neither of those comparisons seem very close to me though. Coherence is much too sloppy for Carruth, and quite a bit more fun.
Like a lot of small-budget and high-concept movies, I think Coherence stretches it's credibility a little bit too far, but manages it better than most. I've heard about how a lot of the production was improvised with the actors loosely following outlines rather than scripting everything out, and I think that's both one of it's biggest strengths (in the moment to moment interactions) and weaknesses (in the overall arcs). It ends up being a solid piece of entertainment though, and there are some genuinely clever ideas that I give them a lot of credit for.